figure, form, shape
姿 centers on the visible form or shape of a person or thing: a figure, appearance, or outward look.
姿 combines 次 (which here likely contributes the sound) with 女 (woman), originally referring to a woman's figure or appearance, later extended to form or shape in general.
A woman 女 standing under a roof-like 次 shape, showing her figure and form.
For シ, imagine a woman's silhouette: she -> シ, her figure clearly outlined.
figure; form; shape
posture; pose; position; stance; carriage (of the body)
(physical) appearance (of a person); one's face and figure
(a person's) appearance from behind; person as seen from behind; back view; retreating figure
full-length mirror
brave figure; valiant figure; heroic figure; gallant figure
standing figure; standing posture
majestic figure; imposing figure; impressive appearance; magnificent appearance
appearing in one's finest clothes; appearing in one's hour of triumph
figure; form; style
ideal situation; ideal world; perfect world; utopia
suited figure; person in a suit
telemark position (in a ski jump landing)
(appearance while) in pajamas (pyjamas)
negotiating posture; attitude to negotiations; negotiating behaviour
flashy appearance
effigy; likeness; portrait; statue
(keeping a) low profile
graceful figure
first wearing (of kimono) in the New Year