Meaning

noun (psychology) a theory that reduces all mental phenomena to simple elements (sensations and feelings) that form complex ideas by association

noun (chemistry) any theory in which all matter is composed of tiny discrete finite indivisible indestructible particles

originEtymology tree Proto-Indo-European *né Proto-Indo-European *n̥- Proto-Hellenic *ə- Ancient Greek ἀ- (a-) Proto-Indo-European *temh₁- Proto-Indo-European *-né- Ancient Greek τέμνω (témnō) Proto-Indo-European *-ós Proto-Hellenic *-ós ▲ Ancient Greek -ος (-os)influ. Ancient Greek -ός (-ós) Ancient Greek *τομός (*tomós) Ancient Greek ἄτομος (átomos)bor. Latin atomusbor. Middle French athomebor.…

Etymology from Wiktionary, CC BY-SA 3.0