prevail, v.i.1To prevail over, against, s.o., sth., an ceann is fearr a fháil ar dhuine, ar rud; buachan ar dhuine, ar rud. The law prevailed, bhí an lá ag an dlí. 2To prevail (up)on s.o. to do sth., tabhairt ar dhuine, a chur ina luí ar dhuine, rud a dhéanamh. He was prevailed upon by his friends to . . ., chuaigh a chairde go bog agus go crua air go . . . 3Tá i réim, faoi réim. A theory that prevails, teoiric atá faoi réim. The conditions now prevailing in France, an saol atá (ag imeacht) sa Fhrainc faoi láthair.