ag·gress (ə-grěs') intr.v.
ag·gressed, ag·gress·ing, ag·gress·es To initiate an attack, war, quarrel, or fight: "America . . . guaranteed that no EC state would aggress against another"(John J. Mearsheimer).
[French agresser, from Latin aggredī, aggress-, to attack : ad-, ad- + gradī, to go; see ghredh- in Indo-European roots.]