pre·vail 
(prĭ-vāl)
(prĭ-vāl)intr.v. pre·vailed, pre·vail·ing, pre·vails
1. To be greater in strength or influence; triumph: The home team prevailed against the visitors. Shouldn't the public interest prevail over an individual's?
2. To be most common or frequent; be predominant: a region where snow and ice prevail.
3. To be in force, use, or effect; be current: an ancient tradition that still prevails.
4. To use persuasion or inducement successfully. Often used with on, upon, or with. See Synonyms at persuade.
[Middle English prevailen, from Old French prevaloir, prevaill-, from Latin praevalēre, to be stronger : prae-, pre- + valēre, to be strong; see wal- in the Appendix of Indo-European roots.]
pre·vailer n.