The definition of ajar refers to something that is slightly opened.(adjective)
Leaving a shoe in the doorway so that is will not shut is an example of a door being ajar.
See ajar in Webster's New World College Dictionary
Origin: ME on char, a-char < OE cier, a turn: see chore
Origin: a- + jar
See ajar in American Heritage Dictionary 4
adverb & adj.
Origin: Middle English on char
Origin: : on, in; see on
Origin: + char, turn (from Old English cierr).
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