ductless gland

gland from which hormones, etc pass directly into the bloodstream, not through a duct 无管腺; 内分泌腺.

dual-control, dual-purpose, duality, dub, dubbin, dubiety, dubious, ducal, duchess, duchy, duck, duck-boards, duck-yard, ducking, duckling, ducks and drakes, duckweed, duct, ductile, ductility, dud, dude, dudgeon, duds, due, due to, duel, duellist, duenna, duet, duff, duffer, duffle (also duffel), duffle bag, duffle-coat, dug, dug-out, duke, dukedom, dulcet,