sup

The symbol for the supremum of a set. Correctly used in the form "sup {some set here}", but commonly found as "sup_{some condition on x} some function of x".

"Sup" is slang, a contraction of "what's up?," though it usually simply substitutes for a greeting formality such as "hi," "hey," or "yo," as 'what's up' has been wont to do. It is most commonly used by youth in very informal contexts. It does not require an actual response and is usually used for efficiency's sake instead of to convey semantic information; if speakers actually wish to inquire about another, they follow up the "sup" with "what's going on," "how's it hanging;" "how're you doing?" Related sayings are wazzzup and wassup, which are more expressive but take longer to say.

Sup (?), v. t. [imp. & p. p. Supped (?); p. pr. & vb. n. Supping.] [OE. soupen to drink, AS. span; akin to D. zuipen, G. saufen, OHG. sfan, Icel. spa, Sw. supa, Dan. sobe. Cf. 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.

© Webster 1913.

Sup, n.

A small mouthful, as of liquor or broth; a little taken with the lips; a sip.

Tom Thumb had got a little sup. Drayton.

© Webster 1913.

Sup, v. i. [See Supper.]

To eat the evening meal; to take supper.

I do entreat that we may sup together.

© Webster 1913.

Sup, v. t.

To treat with supper.

Sup them well and look unto them all. Shak.

© Webster 1913.