Merriam-Webster Collegiate Dictionary - gemmule

 noun  Etymology: French, from Latin gemmula, diminutive of gemma  Date: circa 1828 a small bud:  a. a theoretical particle proposed in the theory of pangenesis that is shed by a somatic cell and contains all the information necessary to reproduce that cell type (as in an offspring)  b. a reproductive bud produced by freshwater and some marine sponges that consists of a usually hardened aggregate of cells