Profound means reaching to the very depths, of thought or of effect. A profound thinker, a profound effect, profound deafness.
Of an idea it means deep and serious; of an effect it means very great — profound changes, profound consequences. In medicine it is a level: profound deafness, profound hearing loss. It also describes the depth of a feeling: profound gratitude, profound sadness. Note profoundly, which is common before adjectives; and profundity, which means both depth and, ironically, a remark trying too hard to be deep.
1adjectiveprofoundReaching to the very depths of thought.
“It sounded profound and meant almost nothing.”
synonyms: deep, penetrating
2adjectivegreatVery great in degree or effect.
“The death of her father had a profound effect on her.”
profound is a degree of depth.
Also accepted in games: deep
The Latin fundus is the bottom, the same bottom that a foundation sits on. Profound goes right down to it and stops there.
hooks ontofoundation
Latin profundus is pro-, forward or down, plus fundus, the bottom — reaching to the bottom. Fundus gives fundamental and foundation, so profound and fundamental are the same depth measured from opposite ends.
Proto-Indo-European
*per-
Latin
profundus — deep, profound
Old French
profont
Anglo-Norman
profound
Middle English
profound
English, today
profound
Built from
From Middle English profound, profounde, from Anglo-Norman profound, from Old French profont, profonde, from Latin profundus (“deep, profound”), from prō + fundus (“bottom; foundation”).
Etymology from Wiktionary, CC BY-SA