v. phr. , informal To waste time; be slow or idle. Grandpa spends so much time sitting and thinking that Grandma accuses him of letting the grass grow under his feet.
LET THE GRASS GROW UNDER ONE'S FEET
Meaning of LET THE GRASS GROW UNDER ONE'S FEET in English
American idioms English vocabulary. Английский словарь американских идиом. 2012