Synonyms: self-generated, self-produced
Definition: originating from the self
Similar words: autogenic, autogenous
Definition: originating within the body
Synonyms: spontaneous, self-generated
Definition: happening or arising without apparent external cause
Usage: spontaneous laughter; spontaneous combustion; a spontaneous abortion
Similar words: unprompted, impulsive
Definition: proceeding from natural feeling or impulse without external stimulus
Usage: an impulsive gesture of affection
Similar words: intuitive
Definition: spontaneously derived from or prompted by a natural tendency
Usage: an intuitive revulsion
Similar words: instinctive, natural
Definition: unthinking; prompted by (or as if by) instinct
Usage: a cat's natural aversion to water; offering to help was as instinctive as breathing