Occasional definitions

Webster's 1828 Dictionary

OCCA'SIONAL, a. s as z.
1. Incidental; casual; occurring at times, but not regular or systematic; made or happening as opportunity requires or admits. We make occasional remarks on the events of the age.
2. Produced by accident; as the occasional origin of a thing.
3. Produced or made on some special event; as an occasional discourse.

WordNet (r) 3.0 (2005)

adj
1: occurring from time to time; "took an occasional glass of wine"
2: occurring or appearing at usually irregular intervals; "episodic in his affections"; "occasional headaches" [syn: episodic, occasional]
3: occurring from time to time; "casual employment"; "a casual correspondence with a former teacher"; "an occasional worker" [syn: casual, occasional]
4: recurring or reappearing from time to time; "periodic feelings of anxiety" [syn: periodic, occasional]

Merriam Webster's

adjective Date: circa 1631 1. a. of or relating to a particular occasion <a budget able to meet occasional demands as well as regular ones> b. created for a particular occasion <occasional verse> 2. acting as the occasion or contributing cause of something 3. encountered, occurring, appearing, or taken at irregular or infrequent intervals <occasional visitors> <an occasional vacation> 4. acting in a specified capacity from time to time <an occasional lecturer> 5. designed or constructed to be used as the occasion demands <occasional furniture>

Oxford Reference Dictionary

adj. 1 happening irregularly and infrequently. 2 made or meant for, or associated with, a special occasion. 3 acting on a special occasion. Phrases and idioms: occasional cause a secondary cause; an occasion (see OCCASION n. 4). occasional table a small table for irregular and varied use. Derivatives: occasionality n. occasionally adv.

Webster's 1913 Dictionary

Occasional Oc*ca"sion*al, a. [Cf.F. occasionnel.] 1. Of or pertaining to an occasion or to occasions; occuring at times, but not constant, regular, or systematic; made or happening as opportunity requires or admits; casual; incidental; as, occasional remarks, or efforts. The . . . occasional writing of the present times. --Bagehot. 2. Produced by accident; as, the occasional origin of a thing. [Obs.] --Sir T. Browne. Occasional cause (Metaph.), some circumstance preceding an effect which, without being the real cause, becomes the occasion of the action of the efficient cause; thus, the act of touching gunpowder with fire is the occasional, but not the efficient, cause of an explosion.

Collin's Cobuild Dictionary

Frequency: The word is one of the 3000 most common words in English. Occasional means happening sometimes, but not regularly or often. I've had occasional mild headaches all my life... Esther used to visit him for the occasional days and weekends. ADJ: usu ADJ n • occasionally He still misbehaves occasionally... ADV: ADV with cl/group, ADV with v

Soule's Dictionary of English Synonyms

a. 1. Incidental, accidental, casual, irregular. 2. Causative, causing.

Moby Thesaurus

accessory, accidental, accompanying, additional, ado, adventitious, afloat, afoot, aleatory, auxiliary, behind the scenes, by-the-way, casual, causal, causative, ceremonial, circumstantial, conditional, constitutive, contingent, current, decisive, determinative, doing, effectual, etiological, eventuating, extra, few, formative, going on, happening, in hand, in the wind, incidental, inessential, infrequent, institutive, intermittent, irregular, nonessential, occurring, odd, off, on, on foot, ongoing, originative, out-of-the-way, parenthetical, part-time, particular, passing, periodic, pivotal, prevailing, prevalent, provisional, random, rare, resultant, ritual, scarce, seldom, side, spare, special, sporadic, supplementary, taking place, uncommon, under way, unessential, unfrequent