Celtic is defined as something related to the Celts, or to a specific Indo-European group of people.(adjective)
A language derived from Indo-European areas is an example of a Celtic language.
The definition of Celtic is a language derived from Indo-European language, or is a person who is a Celt.(noun)
An Indo-European language is an example of Celtic.
See Celtic in Webster's New World College Dictionary
See Celtic in American Heritage Dictionary 4
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