incompetent (suomeksi)

epäpätevä (a: unskilled, lacking normally expected degree of ability)
taitamaton (a: unskilled, lacking normally expected degree of ability)
kyvytön (a: unable to make rational decisions, insane or otherwise cognitively impaired)
inkompetentti (a)
vajaavaltainen (a: oikeustiede / yhteys / unable to make rational decisions, insane or otherwise cognitively impaired)
kykenemätön (a: unable to make rational decisions, insane or otherwise cognitively impaired)
pystymätön (a: unable to make rational decisions, insane or otherwise cognitively impaired)