standing up with

Verb

stand up with (third-person singular simple present stands up with, present participle standing up with, simple past and past participle stood up with)

1. (idiomatic, transitive) To publicly support (someone).
   • [I]t was important as a woman to stand up with other women and raise our voices against the injustice.2001 September 9, Ann Patchett, “Numbers: Women Among Women”, in New York Times, retrieved 26 Nov 2013
2. (idiomatic, transitive) In a wedding ceremony, to serve as best man or as maid of honor or as an official witness for (someone).
   • It was a quiet wedding. . . . Marshall P. Wilder, the humorist, who is a warm personal friend of the bride, stood up with her, and Mr. Cramer, who is connected in an editorial capacity with Frank Leslie's Illustrated Weekly, and Mrs. Cramer, were the only other witnesses.1891 October 6, “Notable Wedding”, in Lawrence Daily Journal, retrieved 26 Nov 2013, page 1
3. (archaic, idiomatic, transitive) To begin to dance with (someone); to dance with (someone).
   • "If Mrs. Gilbert wishes to dance," said he, "I shall have great pleasure, I am sure—for, though beginning to feel myself rather an old married man, and that my dancing days are over, it would give me very great pleasure at any time to stand up with an old friend like Mrs. Gilbert."1815 December (indicated as 1816), [Jane Austen], chapter 38, in Emma: […], volume (please specify |volume=I to III), London: […] [Charles Roworth and James Moyes] for John Murray, →OCLC