a hard brittle brownish gelatin, obtained by boiling to a jelly the skins, hoofs, etc., of animals. when gently heated with water, it becomes viscid and tenaceous, and is used as a cement for uniting substances. the name is also given to other adhesive or viscous substances.-to join with glue or a viscous substance; to cause to stick or hold fast, as if with glue; to fix or fasten.