KanjiJLPT N1
Congeal

congeal, freeze, stiff, be absorbed in

Mnemonic

Standing on ice, a wave of doubt washes over you: is it thick enough to hold your weight? Your legs lock, muscles tighten, and your whole body begins to congeal in place. Frozen by doubt on ice, you become as solid and immovable as the surface beneath you.
Additional thoughts
Doubt on ice is the perfect recipe for congealing — uncertainty makes you freeze both mentally and physically. Picture yourself literally solidifying into a human statue on a frozen lake.
Quick recall
Ice + doubt about its strength makes your entire body congeal rigid in place.

Details

The keyword for 凝 is congeal. This kanji refers to the process of solidifying, thickening, or becoming firm, much like a liquid turning into a solid state. It extends beyond the purely physical to also describe intense concentration or fixation, as when one's gaze becomes frozen on something or when one becomes deeply absorbed in a pursuit. The sense throughout is of something fluid or diffuse gathering together and becoming dense, fixed, or rigid.
On'yomi
ぎょう
Kun'yomi
こ.る、こ.らす、こご.らす、こご.らせる、こご.る