umpire
noun /ˈʌmpaɪə(r)/
  /ˈʌmpaɪər/
(also North American English, informal ump 
 /ʌmp/
  /ʌmp/
)- (in sports such as tennis and baseball ) a person whose job is to watch a game and make sure that rules are not broken
- The umpire’s decision is final.
 
Oxford Collocations DictionaryUmpire is used after these nouns:- baseball
 
Word Originlate Middle English (originally as noumpere) (denoting an arbitrator): from Old French nonper ‘not equal’. The n was lost by wrong division of a noumpere; compare with adder.