adj. & n.
--adj.
1. (often foll. by to + infin.) not qualified or able to perform a particular task or function (an incompetent builder).
2 showing a lack of skill (an incompetent performance).
3 Med. (esp. of a valve or sphincter) not able to perform its function.
--n. an incompetent person.
Derivatives:
incompetence n. incompetency n. incompetently adv.
Etymology: F incomp{eacute}tent or LL incompetens (as IN-(1), COMPETENT)