Pronunciation: (u-kā'zhu-nl),[key] —adj. 1. occurring or appearing at irregular or infrequent intervals; occurring now and then: an occasional headache. 2. intended for supplementary use when needed: an occasional chair. 3. pertaining to, arising out of, or intended for the occasion: occasional verses. 4. acting or serving for the occasion or only on particular occasions.
5. serving as the occasion or incidental cause.