【机】 annular space
snake; ophidian; serpent
【医】 snake
aperture; eye; key point; look; small hole
【医】 eye; oculi; oculo-; oculus; ophthalm-; ophthalmo-; ophthalmos
ophthalmus
crack; crevice; gap; interval; opportunity; rift
【化】 opening
【医】 gap; space; spatia; spatium; split