false colours

British  

plural noun

1. a flag to which one is not entitled, flown esp in order to deceive

   the ship was sailing under false colours

2. an assumed or misleading name or guise

   to trade under false colours

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Example Sentences

The new photographs include images in false colours that clearly show the shape of Carn Glas.

From BBC • Sep. 26, 2023

My whole life has been shuffled through under false colours.

From Ghetto Tragedies by Zangwill, Israel

We came here somewhat under false colours, to try and find out about this murder, and in the hope we might discover some proofs of Captain Mervyn's innocence.

From The Curse of Carne's Hold A Tale of Adventure by Henty, G. A. (George Alfred)

I could only have gone as a professed wizard or prophet—under false colours, in fact.

From Hair-Breadth Escapes The Adventures of Three Boys in South Africa by Adams, H.C.

After the ambush was settled with so much false courage, the business of decoying Mr. Campbell into it was not practicable any other way than by sending out false colours.

From The History of the Life and Adventures of Mr. Duncan Campell A Gentlen, who, tho' Deaf and Dumb, Writes down any Stranger's name at first Sight; by Defoe, Daniel