Germ

Germ \jurm\ , noun;
1. A microorganism, especially when disease-producing; microbe
2. A bud, offshoot, or seed

Germs look kind of cool if you make them colorful! (source)

This word is first attested in 1644 as "bud, sprout" from Middle French germe ("germ (of an egg); bud; seed, fruit; offering"), which derives from Latin germen ("sprout, bud"). I probably ultimately derives from Proto-Indo-European *gen- ("to beget, bear"), which is also the forebear of genus. The sense of "harmful microorganism" is first attested in 1871, which makes sense because that's about the time we started realizing that microorganisms are the cause of disease.