aggressive
ag-gres-sive
adjective
Very determined and forceful in pursuing aims or objectives.
"The company adopted an aggressive marketing strategy."
adjective
Ready or likely to attack; hostile and confrontational.
"The dog displayed aggressive behaviour towards strangers."
adjective
Developing or spreading quickly and harmfully; difficult to control.
"Doctors are treating an aggressive form of cancer."
Thesaurus
Synonyms: strong-growing, invasive, fast-growing, battleful, hostile, vulturine, vulturous, truculent, militant, bellicose, raptorial, scrappy
Antonyms: nonaggressive, unaggressive