UNFIT

unfit

(adjective) not in good physical or mental condition; out of condition; “fat and very unfit”; “certified as unfit for army service”; “drunk and unfit for service”

unfit

(adjective) below the required standards for a purpose; “an unfit parent”; “unfit for human consumption”

bad, unfit, unsound

(adjective) physically unsound or diseased; “has a bad back”; “a bad heart”; “bad teeth”; “an unsound limb”; “unsound teeth”

disqualify, unfit, indispose

(verb) make unfit or unsuitable; “Your income disqualifies you”

Source: WordNet® 3.1

Etymology

Adjective

unfit (comparative unfitter, )

Not fit; not having the correct requirements.

Not fit, not having a good physical demeanor.

Verb

unfit (third-person singular simple present unfits, present participle unfitting, simple past and past participle unfitted)

To make unfit; to render unsuitable, spoil, disqualify.

Source: Wiktionary

Un*fit", v. t. Etym: [1st pref. un- + fit.]

Definition: To make unsuitable or incompetent; to deprive of the strength, skill, or proper qualities for anything; to disable; to incapacitate; to disqualify; as, sickness unfits a man for labor; sin unfits us for the society of holy beings.

Un*fit", a. Etym: [Pref. un- + fit.]

Definition: Not fit; unsuitable.

– Un*fit"ly, adv.

– Un*fit"ness, n.

Source: Webster’s Unabridged Dictionary 1913 Edition