noun, masculine/koˌloɾ de ˌpero ke ˈuʝe/
an nonspecific or nameless color, sometimes especially an unattractive one
“For quotations using this term, see Citations:color de perro que huye.”
Literally, “color of a dog that flees”. Extremely rare compared to similar expressions in neighbouring languages, and thus most likely a calque from one of them, like Catalan color de gos com fuig.