増
ゾウ, ま.す, ま.し, ふ.える, ふ.やす, まし, ます

increase, add, augment, gain, promote

JLPT3 G5 S14 F231

As per 曾# (pile) + 土 earth → pile earth → *pile up*; *add (to)*; *increase*; *gain*; *multiply* → *breed*; *extra*; *increasingly*; *more and more*.

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