Y-

(minuscule: ) is a letter of the Latin alphabet, formed from Y with the addition of a macron (¯).In modern dictionaries and textbooks for Latin and Old English, may be used to indicate a long "y" (IPA: ). In Latin, this only occurs in loanwords.
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Alt. of I-
  

A prefix of obscure meaning, originally used with verbs, adverbs, adjectives, nouns, and pronouns. In the Middle English period, it was little employed except with verbs, being chiefly used with past participles, though occasionally with the infinitive Ycleped, or yclept, is perhaps the only word not entirely obsolete which shows this use.