of, pertaining to, or of the nature of instinct.

prompted by or resulting from or as if from instinct; natural; unlearned

an instinctive will to survive.

adjective

conscious , deliberate , meditated , reasonable , sensible

adjective

accustomed , by seat of one’s pants , congenital , habitual , impulsive , inborn , ingrained , inherent , innate , instinctual , intrinsic , intuitional , intuitive , involuntary , knee-jerk * , mechanical , native , natural , normal , regular , rooted , second-nature , spontaneous , typical , unlearned , unmeditated , unpremeditated , unprompted , unthinking , visceral , automatic , reflex , gut , inbred , unacquired