un bidden (adjective) spontaneous: impulsive, willing
Sinonime: ad-lib,
automatic, break loose,
casual,
down,
extemporaneous, extempore,
free, free spirited, from the hip,
impetuous,
impromptu, improvised,
inevitable,
instinctive, involuntary,
irresistible,
natural, off top of head, off-the-cuff, offhand,
simple, unartful,
unavoidable, unbidden, uncompelled,
unconscious, unconstrained, uncontrived,
uncontrolled, unforced,
unintentional,
unplanned, unpremediated, unprompted,
unsophisticated, unstudied, up front,
voluntaryAntonime: deliberate,
intended,
planned, premeditated