がたっと

がたっとgatatto

adverb

  1. with a clunk
  2. with a clank
  3. the sound of a sudden decrease (in profits, vigor, etc.)

Study it in Yanamino

Data from JMdict, KANJIDIC2 (EDRDG), KanjiVG, CC-CEDICT and Make Me a Hanzi. Sources and licences