ecstatic (adj) enraptured or mystically absorbed; related to or inducing ecstasy
BREAKDOWN: EC- (out) + STAT- (to stand) + -IC (of or pertaining to)
— ecstasy is a state of rapturous delight beyond reason or control; a trance
This word is built on the root STAS-, which means to stand or standing still.
Common STAS- words include ecstasy, system, and thermostat.
More esoteric STAS- words include ananastasia and isostasy.