The Collaborative International Dictionary of English v.0.48:
Minyan \Min*yan"\ (m[-e]n*y[aum]n"), n. (Jewish Relig.) A quorum, or number necessary, for conducting public worship. [Webster 1913 Suppl.]WordNet (r) 3.0 (2006):
minyan n 1: the quorum required by Jewish law to be present for public worship (at least ten males over thirteen years of age)