Webster's Revised Unabridged Dictionary · 1913

Aggress

Aggress ({not transcribed}) , intransitive verb

[Latin aggressus, past participle of aggredi to go to, approach; ad + gradi to step, go, gradus step: compare Old French aggresser. See Grade.]

To commit the first act of hostility or offense; to begin a quarrel or controversy; to make an attack; -- with on.
2.
take the initiative and go on the offensive, as in a game.

Aggress , transitive verb

To set upon; to attack. [Rare]

Aggress , noun

[Latin aggressus.]

Aggression. [Obsolete]
Their military aggresses on others. — Sir M. Hale