there are no flies on(redirected from there are no flies on one)
no flies on (one)
One is very active or works at a fast pace. Alludes to the idea that flies do not or cannot settle on fast-moving animals. There are certainly no flies on Judy. She works so fast that the rest of her team can't keep up with her.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
there are no flies on someone
If you say there are no flies on someone, you mean that they are quick to understand a situation and are not easily deceived. Oh, he was a smart one, all right. There were no flies on him.
Collins COBUILD Idioms Dictionary, 3rd ed. © HarperCollins Publishers 2012
there are no flies on —the person mentioned is very quick and astute.
Early instances of this expression suggest that it originated with reference to cattle who were so active that no flies settled on them. The phrase was noted in the mid 19th century as being very common in Australia as a general expression of approbation. In the USA it could also be used to convey that the person in question was of superior breeding or behaved honestly.
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