a (1)

indefinite article, form of an used before consonants, mid-12c., a weakened form of Old English an "one" (see an). After c. 1600 the -n- also began to vanish before words beginning with a sounded -h-; it still is retained by many writers before unaccented syllables in h- or (e)u- but is now no longer normally spoken as such. The -n- also lingered (especially in southern England dialect) before -w- and -y-through 15c.

It also is used before nouns of singular number and a few plural nouns when few or great many is interposed.

a(2)

as in twice a day, etc., a reduced form of Old English an "on" (see on (prep.)), in this case "on each." The sense was extended from time to measure, price, place, etc.

-a (1)

word-forming element which in English is characteristic of fem. nouns and adjectives of Latin or Greek origin (such as idea, coma, mania, basilica, arena, formula, nebula). From Latin -a (plural -ae) and Greek -a, -ē (plural -ai, Latinized as -ae). The Latin suffix also became Italian -a (plural -e), Spanish -a (plural -as). It is represented in Old English by -u, -e, but even then the suffix was fading and by the time of modern English was totally lost or swallowed into silent final -e-.

It also appears in Romanic words from Latin that have been borrowed into English, such as opera, plaza, armada. It figures in scientific names coined in Modern Latin (amoeba, soda, magnolia, etc.) and is common in geographical names formed according to Latin or Greek models (Asia, Africa, America, Arabia, Florida, etc.)

In English it marks sex only in personal names (Julia, Maria, Alberta) and in a few words from Italian or Spanish where a corresponding male form also is in use (donna, senora).

-a (2)

nominative neuter plural ending of certain nouns and adjectives in Latin and Greek that have been adopted into English (phenomena, data, media, criteria, etc.).

-ability

word-forming element expressing ability, fitness, or capacity, from Latin -abilitas, forming nouns from adjectives ending in -abilis (see -able).

-able

common termination and word-forming element of English adjectives (typically based on verbs) and generally adding a notion of "capable of; allowed; worthy of; requiring; to be ______ed," sometimes "full of, causing," from French -able and directly from Latin -abilis. It is properly -ble, from Latin -bilis (the vowel being generally from the stem ending of the verb being suffixed), and it represents PIE *-tro-, a suffix used to form nouns of instrument, cognate with the second syllables of English rudder and saddle (n.).

A living element in English, used in new formations from either Latin or native words (readable, bearable) and also with nouns (objectionable, peaceable). Sometimes with an active signification (suitable, capable), sometimes of neutral signification (durable, conformable). It has become very elastic in meaning, as in a reliable witness, a playable foul ball, perishable goods. A 17c. writer has cadaverable "mortal."

To take a single example in detail, no-one but a competent philologist can tell whether reasonable comes from the verb or the noun reason, nor whether its original sense was that can be reasoned out, or that can reason, or that can be reasoned with, or that has reason, or that listens to reason, or that is consistent with reason; the ordinary man knows only that it can now mean any of these, & justifiably bases on these & similar facts a generous view of the termination's capabilities; credible meaning for him worthy of credence, why should not reliable & dependable mean worthy of reliance & dependence? [Fowler]

In Latin, infinitives in -are took -abilis, others -ibilis. Hence the variant form -ible in Old French, Spanish, English.

-acea

word-forming element in Modern Latin making names for orders and classes in zoology (Crustacea, Cetacea, etc.), from Latin -acea, neuter plural of -aceus "belonging to, of the nature of" (corresponding to -aceous; enlarged from adjectival suffix -ax, genitive -acis).

The names are thus formally adjectives, Latin animalia "animals" (a neuter plural noun) being understood. Thus Crustacea "shellfish" are *crustacea animalia "crusty animals."

In botany, the suffix is -aceae, from the fem. plural of -aceus, forming orders or families of plants (Rosaceae, etc.) with a presumed plantae "plants," which is a fem. plural.

-acious

compound adjectival word-forming element of Latin origin, attached to verb stems and expressing intensity of action: "given to, inclined to, abounding in," or expressing intensity of physical or mental action, from Latin -aci- (nominative -ax, accusative -acem), noun ending used with verbal stems (see -acea), + -ous. The accompanying nouns are formed in -acity.

-acy

word-forming element making nouns of quality, state, or condition, a confusion in English of three similar suffixes from Latin: 1. in primacy, etc., from Old French -acie and directly from Medieval Latin -acia, Late Latin -atia, making nouns of quality, state, or condition from nouns in -as. 2. in advocacy, etc., from Late Latin -atia, forming nouns of state from nouns in -atus. 3. in fallacy, etc., from Latin -acia, forming nouns of quality from adjectives in -ax (genitive -acis).

-ad

word-forming element of Greek origin appended to nouns and denoting collective numerals (triad, Olympiad) and fem. patronymics (Dryad, Naiad, also, in plural, Pleiades, Hyades), thence also plant family names; from Greek -as (genitive -ados), fem. suffix equivalent to -is.

From its use in Iliad (literally "of Ilion," that is, "Troy;" from Ilias poiesis or oidos "poem of Ilion," the accompanying noun being feminine, hence the termination) it has formed titles of poems in imitation of it (Columbiad, Dunciad.

-ade

word-forming element denoting an action or product of an action, via French, Spanish, or Italian, ultimately from Latin -ata, fem. past participle ending used in forming nouns. The usual form in French is -ée. The parallel form, -ade, came into French about the 13c. via southern Romanic languages (Spanish, Portuguese, and Provençal -ada, Italian -ata), hence grenade, crusade, ballad, arcade, comrade, balustrade, lemonade, etc.

This foreign suffix ade has been so largely imported, and at a time when the French language had still a certain plastic force, that it has been adopted as a popular suffix, and is still employed to form a crowd of new words, such as promenade, embrassade, glissade, bourrade, &c. [Brachet, "Etymological Dictionary of the French Language," Kitchin transl., Oxford, 1882]

Latin -atus, past participle suffix of verbs of the 1st conjugation also became -ade in French (Spanish -ado, Italian -ato) and came to be used as a suffix denoting persons or groups participating in an action (such as brigade, desperado).

-ado

in commando, desperado, tornado, and other words of Spanish and Portuguese origin, "person or group participating in an action," from Latin -atus, past participle suffix of verbs of the first conjugation (see -ade).

-ae

occasional plural suffix of words ending in -a (see a- (1)), most of which, in English, are from Latin nominative fem. singular nouns (or Greek ones brought up through Latin), which in Latin form their plurals in -ae.

-age

word-forming element in nouns of act, process, function, condition, from Old French and French -age, from Late Latin -aticum "belonging to, related to," originally neuter adjectival suffix, from PIE *-at- (source of Latin -atus, past participle suffix of verbs of the first conjugation) + *-(i)ko-, secondary suffix forming adjectives (see -ic).

-al (1)

suffix forming adjectives from nouns or other adjectives, "of, like, related to, pertaining to," Middle English -al, -el, from French or directly from Latin -alis (see -al (2)).

-al (2)

suffix forming nouns of action from verbs, mostly from Latin and French, meaning "act of ______ing" (such as survival, referral), Middle English -aille, from French feminine singular -aille, from Latin -alia, neuter plural of adjective suffix -alis, also used in English as a noun suffix.

-ana

or ana, word-forming element denoting "collection of sayings, gossip, etc. connected with a person or place," early 18c., originally the neuter plural ending of Latin adjectives ending in -anus "pertaining to," from PIE adjectival suffix *-no-.

-ance

word-forming element attached to verbs to form abstract nouns of process or fact (convergence from converge), or of state or quality (absence from absent); ultimately from Latin -antia and -entia, which depended on the vowel in the stem word, from PIE *-nt-, adjectival suffix.

-ancy

word-forming element denoting quality or state, from Latin -antia, forming abstract nouns on past-participle adjectives in -antem, appearing in English mostly in words borrowed directly from Latin (those passing through French usually have -ance or -ence; see -ance).

-ant

agent or instrumental suffix, from Old French and French -ant, from Latin -antem, accusative of -ans, present participle suffix of many Latin verbs.

-ard

also -art, from Old French -ard, -art, from German -hard, -hart "hardy," forming the second element in many personal names, often used as an intensifier, but in Middle High German and Dutch used as a pejorative element in common nouns, and thus passing into Middle English in bastard, coward, blaffard ("one who stammers"), etc. It thus became a living element in English, as in buzzard, drunkard. The German element is from Proto-Germanic -hart/-hard "bold, hardy," from PIE root *kar- "hard."

-ary

adjective and noun word-forming element, in most cases from Latin -arius, -aria, -arium "connected with, pertaining to; the man engaged in," from PIE relational adjective suffix *-yo- "of or belonging to." The neuter of the adjectives in Latin also were often used as nouns (solarium "sundial," vivarium, honorarium, etc.).

-aster

word-forming element expressing incomplete resemblance (such as poetaster), usually diminutive and deprecatory, from Latin -aster, from a suffix forming nouns from verbs ending in Greek -azein; in later Latin generalized as a pejorative suffix, as in patraster "he who plays the father."

-ate (1)

word-forming element used in forming nouns from Latin words ending in -atus, -atum (such as estate, primate, senate). Those that came to English via Old and Middle French often arrived with -at, but an -e was added after c. 1400 to indicate the long vowel. The suffix also can mark adjectives formed from Latin past participals in -atus, -ata (such as desolate, moderate, separate); again, they often were adopted in Middle English as -at, with an -e appended after c. 1400.

-ate (2)

verbal suffix for Latin verbs in -are, identical with -ate (1). Old English commonly made verbs from adjectives by adding a verbal ending to the word (such as gnornian "be sad, mourn," gnorn "sad, depressed"), but as the inflections wore off English words in late Old and early Middle English, there came to be no difference between the adjective and the verb in dry, empty, warm, etc. Thus accustomed to the identity of adjectival and verbal forms of a word, the English, when they began to expand their Latin-based vocabulary after c. 1500, simply made verbs from Latin past-participial adjectives without changing their form (such as aggravate, substantiate) and it became the custom that Latin verbs were Englished from their past participle stems.

-ate (3)

in chemistry, word-forming element used to form the names of salts from acids in -ic; from Latin -atus, -atum, suffix used in forming adjectives and thence nouns; identical with -ate (1).

The substance formed, for example, by the action of acetic acid (vinegar) on lead was described in the 18th century as plumbum acetatum, i.e. acetated lead. Acetatum was then taken as a noun meaning "the acetated (product)," i.e. acetate. [W.E. Flood, "The Origins of Chemical Names," London, 1963]