Left: thread 纟/糸, right: satisfy, to fill 充 (The newborn baby [= child 子 upside down, because it comes with the head first] flounders with his legs 儿 to be 'filled' [= fed] and thus be satisfied. (cf.流)
Mnemonic
Threads are satisfying if they are in a context. (i.e. woven)
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