Entry
  1. Adverb (fukushi), Suru verb

    firmly; solidly; heartily

    Onomatopoeic or mimetic wordsee がっしり

    彼はボディビルが趣味というだけあって体がガシッとしている。
    Bodybuilding is his hobby so he has a very firm tight body with lots of muscle definition.

Also written がしっとがっしとガッシと

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