collodion Highly flammable, colorless or yellowish syrupy solution of pyroxylin, ether, and alcohol, used as an adhesive to close small wounds and hold surgical dressings, in topical medications, and for making photographic plates.
colocynth (bitter apple) Old World vine (Citrullus colocynthis) bearing yellowish, green-mottled fruits the size of small lemons. The pulp of the fruit is a strong laxative.
colombo (calumba) Root of an African plant (Jatrorrhiza palmata, family Menispermaceae) containing columbin; it is used as a tonic called calumba root or colombo root.
colostrum (foremilk) Thin yellowish fluid secreted by the mammary glands at birth, rich in antibodies and minerals. It precedes the production of true milk.
coltsfoot (galax) Eurasian herb (Tussilago farfara), natural