a. (Zool.) Producing yolk, or vitelline substance; -- applied to certain cells (also called nutritive, or yolk, cells) formed in the ovaries of many insects, and supposed to supply nutriment to the developing ova. [ 1913 Webster ]

n. [ See Vitellus. ] (Physiol. Chem.) An albuminous body, belonging to the class of globulins, obtained from yolk of egg, of which it is the chief proteid constituent, and from the seeds of many plants. From the latter it can be separated in crystalline form. [ 1913 Webster ]

[ 1913 Webster ]

a. [ L. vitellus the yolk of an egg. ] (Biol.) Of or pertaining to the yolk of eggs; as, the vitelline membrane, a smooth, transparent membrane surrounding the vitellus. [ 1913 Webster ]