spontaneous, impulsive, instinctive, automatic, mechanical mean acting or activated without deliberation. spontaneous implies lack of prompting and connotes naturalness.

Not expected or planned (Definition of instinctive from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)

Instinctive definition: of, relating to, or of the nature of instinct.. See examples of INSTINCTIVE used in a sentence.

An instinctive feeling, idea, or action is one that you have or do without thinking or reasoning. It's an absolutely instinctive reaction–if a child falls you pick it up.

Definition of instinctive adjective from the Oxford Advanced Learner's Dictionary. based on instinct (= a natural quality that makes somebody/something behave in a particular way), not thought …

Being such by natural inclination rather than conscious effort or study: "Both men were instinctive masters at seizing unexpected openings and turning them into victories" (Nick Kotz).

The adjective instinctive describes something you do without thinking about it. If you have an instinctive desire to help animals, you might automatically stop your car to pick up every stray …