to take (a) part with: to side with, range oneself on the side of (now rare). to take (a) part against: to side against, oppose (now rare).

to take (also †hold) sides, to take a side, and variants: to support one person, group, cause, etc., against another in a conflict or debate…

to take the part of: to take the side of; to support or back up (a person). Also to take a person's part.

intransitive. To take sides; to take part against or with a person. Obsolete.

transitive. To ally oneself with, give one's support to (a particular faction, side, or cause). Obsolete.

transitive (reflexive) in same sense. Frequently with with.

Scottish. transitive. To take the part of, side with. Obsolete.

transitive. Scottish. To side with, take the side of. Cf. party, v. 1b. Obsolete.