mucilage

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A sticky substance used as an adhesive.
2. n. A gummy substance obtained from certain plants.

Century Dictionary and Cyclopedia

1. n. Moldi-ness; mustiness; rottenness; a slimy mass.
2. n. Gum extracted from the seeds, roots, and bark of plants. It is found universally in plants, but much more abundantly in some than in others. The marsh-mallow root, tubers of orchids, the bark of the lime and elm, the seeds of quinces and flax, are examples of plant-products rich in this substance. In the arts the name is applied to a great variety of sticky and gummy preparations, some of which are merely thickened aqueous solutions of natural gum, which is easily extracted from vegetable substances by hot water; while others are preparations of dextrine, glue, or other adhesive materials, generally containing some preservative substance or compound, as creosote or salicylic acid.
3. n. In chem., the general name of a group of carbohydrates, having the formula C₆H₁₀O₅n. The mucilages have the common property of swelling enormously in water, so that they are in a condition near to solution, leaving no jelly-like mass as many gums do. Members of the group differ greatly in properties, some being closely related to the gums, others to cellulose. Their chemical constitution is not yet determined.

Wiktionary

1. n. A thick gluey substance (gum) produced by many plants and some microorganisms.

GNU Webster's 1913

1. n. (Bot. Chem.) A gummy or gelatinous substance produced in certain plants by the action of water on the cell wall, as in the seeds of quinces, of flax, etc.
2. n. An aqueous solution of gum, or of substances allied to it; a glue; a liquid adhesive

WordNet 3.0

1. n. a gelatinous substance secreted by plants
2. n. cement consisting of a sticky substance that is used as an adhesive