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.
Hear it pronounced