The definition of ally is to join another in a mutually beneficial relationship.(verb)
An example of ally is a couple who gets married.
Ally is defined as an individual, country or organization that unites with another.(noun)
An example of an ally is Britain to the US in World War II.
In the field of biology, ally is defined as two things that have an evolutionary relationship.(noun)
An example of a vegetable that is an ally is cabbage as compared to Brussel sprouts.
See ally in Webster's New World College Dictionary
Origin: ME alien < OFr alier < L alligare < ad-, to + ligare, to bind: see ligature
noun pl. allies
See ally in American Heritage Dictionary 4
verb al·lied, al·ly·ing, al·lies verb, transitive
Origin: Middle English allien
Origin: , from Old French alier
Origin: , from Latin alligāre, to bind to; see alloy.
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