Definition of colloid

• a. - Resembling glue or jelly; characterized by a jellylike appearance; gelatinous; as, colloid tumors.
• n. - A substance (as albumin, gum, gelatin, etc.) which is of a gelatinous rather than a crystalline nature, and which diffuses itself through animal membranes or vegetable parchment more slowly than crystalloids do; -- opposed to crystalloid.
• n. - A gelatinous substance found in colloid degeneration and colloid cancer.