to work very hard; to work like a beaver
"I became an investment banker after college, and now I work like a dog."

"I'm too old to work like a dog"
by boardshop July 1, 2008
"Man, I've been working like a dog", he muttered into the phone, his feet up, eyes on the game, the bag of Doritos on his chest almost empty. There must have been a time, long ago, he imagined, when dogs spent their lives herding cattle from sunrise to sunset, but any actual 21st century dog he knew was lazier than The Dude.
by Monkey's Dad March 1, 2020