constellation (representing Aesculapius), 1650s, from Latin, from Greek ophioukhos, literally "holding a serpent," from ophis "serpent" (see ophio-) + stem of ekhein "to hold, have, keep" (see scheme, n.). The constellation is equatorial, and Milton's "Ophiuchus huge in th' Arctick Sky" ("Paradise Lost") is a rare lapse for a poet who generally knew his astronomy.