protium

Also contains definitions of: protide, protio
https://doi.org/10.1351/goldbook.P04903
A specific name for the atom 1H. The cation1H+ is a proton, the species 1H is a protide anion, and 1H is the protio group. The word proton should not be used for H+ in its natural abundance.
Source:
PAC, 1988, 60, 1115. 'Names for hydrogen atoms, ions, and groups, and for reactions involving them (Recommendations 1988)' on page 1116 (https://doi.org/10.1351/pac198860071115)