Word Study
retro-
CIDE DICTIONARY
retro-, [L. retro, adv., backward, back. Cf. Re-.].
A prefix or combining form signifying backward, back; as, retroact, to act backward; retrospect, a looking back. [1913 Webster]
OXFORD DICTIONARY
retro-, comb. form 1 denoting action back or in return (retroact; retroflex).
2 Anat. & Med. denoting location behind.
2 Anat. & Med. denoting location behind.
Etymology
L retro backwards
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