On occasion

Occasion Oc*ca"sion ([o^]k*k[=a]"zh[u^]n), n. [F. occasion, L. occasio, fr. occidere, occasum, to fall down; ob (see {Ob-}) + cadere to fall. See {Chance}, and cf. {Occident}.] 1. A falling out, happening, or coming to pass; hence, that which falls out or happens; occurrence; incident; event. [1913 Webster]

The unlooked-for incidents of family history, and its hidden excitements, and its arduous occasions. --I. Taylor. [1913 Webster]

2. A favorable opportunity; a convenient or timely chance; convenience. [1913 Webster]

Sin, taking occasion by the commandment, deceived me. --Rom. vii. 11. [1913 Webster]

I'll take the occasion which he gives to bring Him to his death. --Waller. [1913 Webster]

3. An occurrence or condition of affairs which brings with it some unlooked-for event; that which incidentally brings to pass an event, without being its efficient cause or sufficient reason; accidental or incidental cause. [1913 Webster]

Her beauty was the occasion of the war. --Dryden. [1913 Webster]

4. Need; exigency; requirement; necessity; as, I have no occasion for firearms. [1913 Webster]

After we have served ourselves and our own occasions. --Jer. Taylor. [1913 Webster]

When my occasions took me into France. --Burke. [1913 Webster]

5. A reason or excuse; a motive; a persuasion. [1913 Webster]

Whose manner was, all passengers to stay, And entertain with her occasions sly. --Spenser. [1913 Webster]

{On occasion}, (a) in case of need; in necessity; as convenience requires. ``That we might have intelligence from him on occasion,'' --De Foe. (b) occasionally; from time to time; now and then. [1913 Webster +PJC]

Syn: Need; incident; use. See {Opportunity}. [1913 Webster]