'Yún chèn' literally combines 匀 (yún), meaning 'even', 'uniform', or 'balanced', and 称 (chèn), meaning 'to match', 'to suit', or 'to be proportionate'. Together, they describe something whose parts are harmoniously balanced in size, shape, or distribution — neither too large nor too small, too heavy nor too light. It emphasizes visual or structural harmony rather than mere symmetry.

This term is frequently used to describe physical appearance: human bodies, animal forms (e.g., horses, birds, or dogs bred for show), sculptures, architecture, or even handwriting. While it can occasionally apply to abstract concepts like 'a well-balanced diet', its primary usage is concrete and perceptual — referring to observable proportions. It carries a positive, appreciative connotation, suggesting aesthetic refinement and natural grace.