To hurry up and get moving. Often used as an imperative. The movie is starting in 15 minutes. Look lively! You'd better look lively if you're going to catch your bus.
To pay attention; to be vigilant. Look sharp, or you'll get hit in the head with a soccer ball! Look sharp! There's a hole up ahead!
Get moving, be alert, as in The coach told the team they would have to look sharp if they wanted to win. This colloquial expression, dating from the early 1700s, originally meant "to keep a strict watch" but acquired its present sense in the early 1800s.
look livelyused to tell someone to be quick in doing something. informal
A variant of this phrase is look alive , but this is now rather dated.
look sharpbe quick.
1953 Margaret Kennedy Troy Chimneys I had…begun an idle flirtation with Maria, … then, perceiving that I should be caught if I did not look sharp, I kept out of her way.