/kown'teuhr vayl"/ , v.t.
1. to act or avail against with equal power, force, or effect; counteract.
2. to furnish an equivalent of or a compensation for; offset.
3. Archaic. to equal.
v.i.
4. to be of equal force in opposition; avail.
[ 1350-1400; ME contrevailen countrevail-, tonic s. (subj.) of countrevaloir to equal, be comparable to contra valere to be of worth against (someone or something). See COUNTER-, -VALENT ]
Syn. 1. counterbalance, counterpoise, neutralize.