photoelectron vs negatron

photoelectron and negatron both are nouns.

Word	Noun	Adjective	Verb	Adverb
photoelectron	Yes	No	No	No
negatron	Yes	No	No	No

As nouns, negatron is a hypernym of photoelectron; that is, negatron is a word with a broader meaning than photoelectron:

photoelectron: an electron that is emitted from an atom or molecule by an incident photon
negatron: an elementary particle with negative charge

Other hypernyms of photoelectron include electron.

photoelectron (noun)	negatron (noun)
an electron that is emitted from an atom or molecule by an incident photon	an elementary particle with negative charge