The definition of retro is of a past time.(adjective)
An example of retro used as an adjective is in the phrase "retro clothes," which means clothes of a style in the past.
See retro in Webster's New World College Dictionary
Origin: L < retro, backward < re-, back + -tro, as in intro-
See retro in American Heritage Dictionary 4
Origin: Latin retrō-
Origin: , from retrō, backward, behind; see re- in Indo-European roots.
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