4 The tail wags the dog comentada em 15/06/2020 18:39 #VAILAEFALA! Alice.V em 15/06/20 17:06 comentada em 15/06/2020 18:39 All languages have a set of animals inspired metaphors that make their way into current usage in a pre set sentence or cluster of words, called idioms (expressões idiomáticas). English is rich in those, and it comes in handy to get familiar with them.This idiom refers to the fact that dogs tend to wag their tails enthusiastically when happy. But the sentence actually means that a small or lesser part (of a project, company, for example) is controlling the whole operation.If you say that “the tail is wagging the dog”, you mean that a small or unimportant part of something is becoming too important and is taking undue or disproportionate control of the whole thing.