Căs'ū-al, a.

adjective

(kăzh'ū-al), a. [Lat. casualis, from casus, fall, accident, from cadere, to fall; Pr., Sp., & Pg. casual, It. casuale, Fr. casuel.]

Happening or coming to pass without design, and without being foreseen or expected; accidental; fortuitous; coming by chance. “Casual breaks in the general system.” W. Irving.
Coming without regularity; occasional; incidental; as, casual expenses.

Syn.—Accidental; fortuitous; incidental; occasional; contingent.