instincts Definition

a natural or inherent aptitude, impulse, or capacity

a largely inheritable and unalterable tendency of an organism to make a complex and specific response to environmental stimuli without involving reason

behavior that is mediated by reactions below the conscious level

an innate and unconscious tendency toward self-destruction postulated in psychoanalytic theory to explain aggressive and destructive behavior not satisfactorily explained by the pleasure principle —called also Thanatos

an aggressive tenacious urge for domination in a struggle to attain a set goal