From ad- + atom, meaning "adsorbed atom".
Formed from ad- + atom
Proto-Indo-European *h₂éd ‘near, at’
Proto-Italic *ad ‘toward, to, on, up to, for’
Latin ad ‘to, towards’
English ad-
Proto-Indo-European *temh₁- ‘to cut’
…
Ancient Greek ἄτομος ‘indivisible’
Latin atomus ‘smallest particle’
Middle French athome
Middle English attome
English atom
The story
From ad- + atom, meaning "adsorbed atom".
Today it means
noun An atom that lies on a crystal surface
Language periods are conventional ranges, not dates for this word.
Etymograph / adatom
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