Webster's Revised Unabridged Dictionary · 1913

Sup

Sup (sup) , transitive verb

[Old English soupen to drink, Anglo-Saxon sūpan; akin to Dutch zuipen, German saufen, Old High German sūfan, Icelandic sūpa, Swedish supa, Danish sobe. Compare Sip, Sop, Soup, Supper.]

To take into the mouth with the lips, as a liquid; to take or drink by a little at a time; to sip.
There I'll sup Balm and nectar in my cup. — Crashaw

Sup , noun

A small mouthful, as of liquor or broth; a little taken with the lips; a sip.
Tom Thumb had got a little sup. — Drayton

Sup , intransitive verb

[See Supper.]

To eat the evening meal; to take supper.
I do entreat that we may sup together. — Shakespeare

Sup , transitive verb

To treat with supper. [Obsolete]
Sup them well and look unto them all. — Shakespeare