up to no good


Also found in: Acronyms, Wikipedia.

add up to

To equal or amount to something. The cash in the drawer doesn't add up to the amount of sales we made today. These new details do not add up to the story the witnesses told us.
See also: add, up

up to no good

Engaging in malicious or nefarious behavior. Primarily heard in UK, Australia. I'm worried that my daughter's boyfriend is up to no good—he always seems to be involved in some bizarre scheme. What are you boys whispering about? You're up to no good, aren't you?
See also: good, up

up to no good

Fig. doing something bad. I could tell from the look on Tom's face that he was up to no good. There are three boys in the front yard. I don't know what they are doing, but I think they are up to no good.
See also: good, up