The Collaborative International Dictionary of English v.0.48:
xxv \xxv\, adj. The Roman number representing twenty-five. Syn: twenty-five, 25. [WordNet 1.5]WordNet (r) 3.0 (2006):
xxv adj 1: being five more than twenty [syn: twenty-five, 25, xxv] n 1: the cardinal number that is the sum of twenty-four and one [syn: twenty-five, 25, XXV]