/ əˈlaɪəns; NAmE / noun
1.
alliance (with sb/sth) | alliance (between A and B) an agreement between countries, political parties, etc. to work together in order to achieve sth that they all want :
to form / make an alliance
The Social Democrats are now in alliance with the Greens.
2.
a group of people, political parties, etc. who work together in order to achieve sth that they all want
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WORD ORIGIN
Middle English : from Old French aliance , from alier to ally , from Latin alligare bind together, from ad- to + ligare to bind.