unsportsmanlike

Definitions of unsportsmanlike
1

adj violating accepted standards or rules

“fined for unsportsmanlike behavior”
Synonyms:
cheating, dirty, foul, unsporting
unfair, unjust
not fair; marked by injustice or partiality or deception

Sign up, it's free!

Whether you're a student, an educator, or a lifelong learner, Vocabulary.com can put you on the path to systematic vocabulary improvement.