english
1
general::
Set in direct opposition or competition, as in The civil war pitted brother against brother. This idiom alludes to setting fighting cocks or dogs against one another in a pit. [Mid-1700s]
American Heritage Idioms
2
general::
Phrase(s): pit someone or something against someone or something to set someone or something in opposition to someone or something. • The rules of the tournament pit their team against ours. • John pitted Mary against Sally in the tennis match.
McGrawhill's American Idioms And Phrasal Verbs