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to become thin; to lose weight; to slim
to become impoverished (of soil); to become sterile; to become infertile; to become barren
食事を抜くと体が瘠せる。
Skipping meals makes the body lose weight.
瘠せた土地では作物が育たない。
Crops won't grow in barren soil.
夏の間にかなり瘠せた。
I lost quite a bit of weight during the summer.