Where does “mentally” come from?

Mentally comes from English mental, from Latin mentum, from Proto-Indo-European men- meaning "to think," combined with Latin mens also from Proto-Indo-European men-, with the suffix -ly ultimately tracing to Proto-Indo-European ḱóm.

mentally (English): In a mental manner; an idea thought out in one's...

Definitions

  1. In a mental manner; an idea thought out in one's...

Ancestry of “mentally”, step by step

StepLanguageWordMeaning
1EnglishmentalOf or relating to the mind or an intellectual...
2English-álOf or pertaining to. Adjectival suffix appended to various words, often nouns, to produce an adjective form. Often added to words of Latin origin, but used with other words also
3EnglishaldehydeAny of a large class of reactive organic...
4GermanAldehydaldehyde
5Latinalcoholkohl, collyrium, stibium; any other powder...
6Andalusian Arabicكُحُول
7Arabicكحلantimony; kohl, stibnite; black coloring of the...
8Arabicكُحْلantimony; kohl, stibnite
9Akkadianguḫlumkohl, antimony paste
Every word from Akkadian guḫlum
mentally — Etymology, Origin & Word History | Etymology Explorer