molecule

Where does the word "molecule" come from? It comes from New Latin molecula, and was adopted directly into English (1670s).

Molecule’s story begins in New Latin: molecula meant “a small mass.” A diminutive of moles (mass), literally a small mass. It reached English by 1670s as molecule. French 'molécule', 'little mass', from Latin 'moles'; Avogadro distinguished molecules from atoms in 1811. Today, molecule means the smallest unit of a chemical compound that retains its properties.

1. Stage 1 · New Latin · 1600s molecula "a small mass", a diminutive of moles (mass), literally a small mass.
2. Stage 2 · English · 1670s molecule "the smallest unit of a chemical compound", French 'molécule', 'little mass', from Latin 'moles'; Avogadro distinguished molecules from atoms in 1811.