casual
/ˈka-zhə-wəl/
adjective
subject to, resulting from, or occurring by chance
occurring without regularity : occasional
employed for irregular periods
a casual meeting
accidental fortuitous casual contingent mean not amenable to planning or prediction. accidental stresses chance. fortuitous so strongly suggests chance that it often connotes entire absence of cause.
noun
a casual or migratory worker
an officer or enlisted person awaiting assignment or transportation to a unit
noun
a temporary accumulation of water not forming a regular hazard of a golf course