pant:  It is the shock that makes you ‘gasp’ that lies behind the word pant. It is closely related to English fancy, fantasy, and phantom. It comes from Anglo-Norman *panter, a condensed version of Old French pantaisier ‘gasp’. This in turn went back to Vulgar Latin phantasiāre ‘gasp in horror, as if at a nightmare or ghost’, a derivative of Latin phantasia ‘apparition’ (source of English fancy and fantasy and first cousin to phantom). => fancy, fantasy, phantom
mid-15c., perhaps a shortening of Old French pantaisier "gasp, puff, pant, be out of breath, be in distress" (12c.), probably from Vulgar Latin *pantasiare "be oppressed with a nightmare, struggle for breathing during a nightmare," literally "to have visions," from Greek phantasioun "have or form images, subject to hallucinations," from phantasia "appearance, image, fantasy" (see phantasm). Related: Panted; panting.