Other forms: underdogs
The underdog is the side everyone expects to lose. Back the underdog, a clear underdog, the underdog won.
People support them out of all proportion, which researchers have measured and called the underdog effect: audiences shift towards whoever is losing. Teams sometimes claim the label deliberately, because it lowers what is expected of them.
1noununderdogThe side everyone expects to lose.
“Everyone was cheering for the underdog, a small village team playing a professional club.”
underdog is a competitor.
Middle English
dogge
English
dog
English, today
underdog
Built from
From under- + dog. dog comes from Middle English dogge. Middle English dogge (akin to Scots dug), from Old English dogga, docga, of unknown origin. The original meaning seems to have been a common dog, as opposed to a well-bred one, or something like 'cur', and perhaps later came to be used for stocky dogs. Possibly a pet-form diminutive with suffix -ga (compare frocga (“frog”), picga (“pig”)), appended to a base dog-, doc- of unclear origin and meaning. One possibility is Old English dox (“dark, swarthy”) (compare frocga from frox). Another proposal is that it derives from Proto-West Germanic dugan (“to be suitable”), the origin of Old English dugan (“to be good, worthy, useful”), English dow, Dutch deugen, German taugen. The theory goes that it could have been an epithet for dogs, commonly used by children, meaning "good/useful animal". Another one is that it is related to docce (“stock, muscle”), from dokkā (“round mass, ball, muscle, doll”), whence dock (“stumpy tail”).
Etymology from Wiktionary, CC BY-SA