adjective
(archaic, of a person) Late, tardy, overdue, behind (in accomplishing a task, etc.).
(archaic, of a task or the object of a task) Not at the expected point of completion.
(archaic) Behind (someone or something moving, a trend, etc.), lagging behind, not keeping up.
(archaic) Behind in paying a debt; in arrears.
(archaic) Not having enough of, lacking (in something).
(dated) Inferior, less advanced (compared with someone in something).
adverb
(archaic) Belatedly, tardily.
(archaic) In debt, or in arrears.