Of, pertaining to, or employing a coalition(adjective)
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Use "coalitionary" in a sentence
"Governments in Israel reflect coalitionary power relations and are the highest decision-making forum."
"Liverpool, except that Mr. Huskisson and some two or three of the coalitionary whigs, were retained."
"He asserts that both male humans and chimpanzees, our closest genetic relatives, are "natural warriors" with an innate predisposition toward "coalitionary killing," which dates back to our common ancestor."