Definition - Adding a letter or syllable to the beginning of a word.

Example -
A-camping we will go!

Etymology -
In Greek the word literally means "a setting before."
Note: The word preposition was coined as a loan translation of the word prothesis.

Oxford English Dictionary -
Its first citation in its grammatical sense is from 1870:
"Real prothesis is pretty common in Greek."
(March Ags. Gram. '48. 31)

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