Abbreviation of undersize. / Abbreviation of unserviceable.

Initialism of Upper Sorbian.

Initialism of United States.

(psychology) Initialism of unconditioned stimulus.

Alternative spelling of U.S. of A.

Alternative spelling of µs: microsecond

(rare) Alternative form of u's.

Contraction of us is.

(personal) Me and at least one other person; the objective case of we. / (Commonwealth of Nations, colloquial, chiefly with give) Me. / (Northern England) Our. / (Tyneside) Me (in all contexts).

The speakers/writers, or the speaker/writer and at least one other person.