expression
extremely lazy; won't lift a finger
Idiomatic expression describing someone so lazy they won't even turn a vertical object horizontal—i.e., they won't do the simplest task. Often used hyperbolically. Compare with 横の物を縦にもしない, which has the same meaning.
See also: 横の物を縦にもしない
彼は縦の物を横にもしない怠け者だ。
He's so lazy he won't even lift a finger.
休みの日は縦の物を横にもしないでゴロゴロしている。
On my days off, I just laze around without doing a thing.
The expression literally means 'not even turning a vertical thing horizontal,' implying an extreme unwillingness to perform even the simplest action. The exact origin is uncertain, but it is a set phrase in Japanese.