be clear, serene, cold, skilful
冴 centers on a sharp, clear state: the crisp clarity of cold air, a serene mind, or a skilful, polished ability. The meanings all share the idea of something being honed to a clear, distinct edge.
冴 is the modern simplified form of 冱. It combines 冫 (ice) with 牙, which likely contributes the sound. The older form 冱 used 互 instead of 牙. The exact historical development of the 牙 component is uncertain.
The ice radical 冫 brings the cold, and 牙 looks like a sharp fang. Together, picture a cold, clear winter night so sharp it feels like an icy fang piercing the air—everything is crisp, serene, and skilfully sharp.
For ゴ, imagine a cold, serene go master sitting by an icy pond, perfectly still and clear-minded: go -> ゴ, and the scene is as sharp and clear as the kanji's meaning.
clearness; clarity
to be clear (of a sight, sound, colour, etc.); to be bright; to be vivid; to be crisp
dull; dreary; sullen; depressed
clearly; brightly; freshly
cheerful (look); healthy (complexion)
cheerful (look); healthy (complexion)
to be clear; to be distinct; to be precise
to clear gradually; to get cold gradually
to shine clearly
to be very clear
extreme cold
to be wide-awake; to be wakeful; to be unable to sleep
dexterity; skill
bright intelligence