Microbe (4)
'microbe' is the definition.
(synonyms)
This is all the clue.
(Other definitions for germ that I've seen before include "Start of an idea" , "One causing disease" , "Rudiment" , "Shoot" , "starting point" .)
'microbe' is the definition.
(thesaurus)
This is all the clue.
(Other definitions for bacterium that I've seen before include "Micro-organism that can cause disease" , "germ?" , "health risk?" , "Fundamental" .)