1. y- a prefix occurring in certain obsolete words (iwis) and esp. in archaic past participles (yclad; yclept).
Etymology: (ME y-, i- (reduced var. a-), OE ge-, prefix with perfective, intensifying, or collective force; c. OFris, OS ge-, gi-, OHG ga-, gi, Go ga-)
Definition of 'y-'
Webster Dictionary
1. y- alt. of I-
2. y- 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
Definitions of y- 
