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allied; allying
Definition of ally
(Entry 1 of 3)
: to form or enter into an alliance two factions allying with each other
ally
noun plural allies
Definition of ally (Entry 2 of 3)
1 : a sovereign or state associated with another by treaty or league
America and its allies
2 : one that is associated with another as a helper : a person or group that provides assistance and support in an ongoing effort, activity, or struggle
a political ally She has proven to be a valuable ally in the fight for better working conditions. —often now used specifically of a person who is not a member of a marginalized or mistreated group but who expresses or gives support to that group The storyline on "Glee" captures something larger that we are seeing with a new generation of allies (allies are people who support LGBT rights but aren't LGBT themselves).— David M. Hall
3 : a plant or animal linked to another by genetic or taxonomic proximity
ferns and their allies
-ally
adverb suffixDefinition of -ally (Entry 3 of 3)
: -ly entry 2 terrifically —in adverbs formed from adjectives in -ic with no alternative form in -ical
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Time Traveler for ally
The first known use of ally was in the 14th century
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