あしもとからとりがたつ

足元から鳥が立つ

表記・読み：あしもとからとりがたつ

1. 1

   for something unexpected to happen (to someone or something one is close to)

   expressions (phrases, clauses, etc.)五段動詞（つ）idiomatic expression
2. 2

   (deciding to do something) abruptly; at the turn of a dime

   expressions (phrases, clauses, etc.)usu. as 足元から鳥が立つようにidiomatic expression