1. Biology A small mass of protoplasm or cells from which a new organism or one of its parts may develop.
2. The earliest form of an organism; a seed, bud, or spore.
3. A microorganism, especially a pathogen.
4. Something that may serve as the basis of further growth or development: the germ of a project.
[Middle English, bud, from Old French germe, from Latin germen; see genə- in the Appendix of Indo-European roots.]
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