There are 2 main definitions of ally in English:


Line breaks: ally
Pronunciation: /ˈalʌɪ

noun (plural allies)

1A state formally cooperating with another for a military or other purpose: debate continued among NATO allies
More example sentences
  • Japan is, for all intents and purposes, our strongest ally in Asia at the moment.
  • Many Taiwanese see those two countries as the island's most likely allies in any military conflict with China.
  • The Philippines and Thailand are military allies of the U.S. in Southeast Asia.
1.1A person or organization that cooperates with or helps another in a particular activity: he was forced to dismiss his closest political ally
More example sentences
  • Genuine reformers will look to teachers and teacher organizations as their allies.
  • Within my global responsibilities, the legal department was a close ally and business partner.
  • The two organisations have key allies and it s reassuring for economic development.
associate, colleague, friend, confederate, partner, supporter, accomplice, helper, accessory, abetter
1.2 (the Allies) The countries that fought with Britain in the First and Second World Wars: they were caught between the German army of occupation and the advancing Allies
More example sentences
  • Many Jews had fought for the Allies during World War Two and had developed their military skills as a result.
  • It was the first battle won by the Allies in World War Two and Hitler never won a battle after that.
  • Rochdale could be justly proud of the role it played in helping the Allies to victory in World War Two.


Pronunciation: /also əˈlʌɪ
(allies, allying, allied) [with object] (ally something to/with) Back to top  
1Combine or unite a resource or commodity with (another) for mutual benefit: he allied his racing experience with his father’s business acumen
More example sentences
  • Garry Hay is an integral part of the side as he allies defensive duties with his non-stop attacking forays down the flanks.
  • I also believe such a shift would be good for the nationalist brand: it would ally the party with the quality of dynamism, while showing commitment to personal as well as national ‘freedom’.
  • She had proved a good leader, allying her people with the underground, yet keeping the government in power in complete ignorance of her true alliance.
combine, marry, couple, merge, amalgamate, join, pool, fuse, weld, knit
1.1 (ally oneself with) Side with or support: he allied himself with the forces of change
More example sentences
  • On the other side, advocates of indigenous authors allied themselves with partisans of free trade and international copyright, claiming universal natural rights of authorship.
  • Since the families you ally yourself with in marriage determine your level of access to credit, education, food, housing, and a host of other goods, loss of reputation is a disaster.
  • Moderate Conservatives will prefer not to ally themselves with those views and will stay at home.
unite, join, join up, join forces, band together, go into partnership, team up, combine, collaborate, side, align oneself, league, go into league, affiliate, confederate, form an alliance, throw in one's lot, make common cause


Middle English (as a verb): from Old French alier, from Latin alligare 'bind together', from ad- 'to' + ligare 'to bind'; the noun is partly via Old French alie 'allied'. Compare with alloy.

Definition of ally in: