Game concept
Physical Trait
The game also links it as Physical Traits.
From the game's encyclopedia
A Physical Trait is a descriptor of a physical Trait tied to their appearance or behavior, and the level of intellect a character has. Many physical features affect how Attracted others are to them.
They are often Congenital, thus gained at birth and permanent.
The game's text for patch 1.20.1.2. Words in blue are entries of the encyclopedia: hover one to read it, as in the game.
Physical Trait is an entry of Crusader Kings III's in-game encyclopedia. The game explains it: "A Physical Trait is a descriptor of a physical Trait tied to their appearance or behavior, and the level of intellect a character has." It is part of Trait. The game also links it as Physical Traits. Patch 1.20.1.2, from game/common/game_concepts/00_game_concepts.txt and game/localization/english/game_concepts_l_english.yml.
Source: game/common/game_concepts/00_game_concepts.txt, game/localization/english/game_concepts_l_english.yml and the English localisation, Crusader Kings III 1.20.1.2.