A variant of Straiten.

To make straight; to reduce from a crooked to a straight form.

To make right or correct; to reduce to order; as, to straighten one's affairs; to straighten an account.

put (things or places) in order; "Tidy up your room!"

straighten by unrolling; "roll out the big map"

get up from a sitting or slouching position; "The students straightened when the teacher entered"

straighten up or out; make straight