Main Entry: ¹de·fec·tive

Pronunciation: \di-ˈfek-tiv\

Function: adjective

Date: 14th century

1 a : imperfect in form or function : faulty <a defective pane of glass> b : falling below the norm in structure or in mental or physical function <defective eyesight>
2 : lacking one or more of the usual forms of grammatical inflection <must is a defective verb>

— de·fec·tive·ly adverb

— de·fec·tive·ness noun