Given without an equivalent or recompense; conferred without valuable consideration; granted without pay, or without claim or merit; not required by justice
Not called for by the circumstances; without reason, cause, or proof; adopted or asserted without any good ground; as, a gratuitous assumption
If you describe something as gratuitous, you mean that it is unnecessary, and often harmful or upsetting. There's too much crime and gratuitous violence on TV. his insistence on offering gratuitous advice. + gratuitously gra·tui·tous·ly They wanted me to change the title to something less gratuitously offensive. said or done without a good reason, in a way that offends someone = unnecessary (gratuitus, from gratus; GRATEFUL)