expression, ichidan verb
sleep like a log; sleep like a baby
Idiomatic expression meaning to sleep very deeply and soundly, as if one were as heavy and unmoving as mud.
See also: 泥のように眠る
昨日は疲れていて、泥のように寝た。
I was so tired yesterday that I slept like a log.
彼は泥のように寝ていて、地震にも気づかなかった。
He was sleeping like a log and didn't even notice the earthquake.