Wiktionary
n. a proponent of war or military intrusiveness
WordNet
Wikipedia
A war hawk, or simply hawk, is a term used in politics for someone favoring war in a debate over whether to go to war, or whether to continue or escalate an existing war. War hawks are the opposite of doves. The terms are derived by analogy with the birds of the same name: hawks are predators that attack and eat other animals, whereas doves mostly eat seeds and fruit and are historically a symbol of peace.
Usage examples of "war hawk".
Bitter, of Chicago, was injured doing was Nstrafing the huge Jap air base at Chiengmai, Thailand, in a worn out Curtiss P-40B War hawk, an aircraft the Chinese and their American volunteer pilots were able to fly only because the British turned them down as obsolescent for service against the Germans in Europe.
Essex, however, became more of a war hawk than ever, having tasted the delights of victory.