is-

is-

1. Alternative form of iso-, before a vowel.

• “is-”, in Collins English Dictionary.
• “is-”, in Merriam-Webster Online Dictionary, Springfield, Mass.: Merriam-Webster, 1996–present.
• “is-”, in OneLook Dictionary Search.

• s͞i, Si., S. I., SI, S.I., si, Si

is- (except before s ish-, class I second-person singular)

1. the subject of an active transitive verb

   you, thou

2. the subject of an intransitive active verb

   you, thou

3. the subject of a negative imperative verb

   Issakopōlinna!

   Don't bite me!

From Proto-Brythonic *is, from Proto-Celtic *ɸīssu. Related to a-is (“below, lower”) and isel (“low”). Compare Welsh is-

is-

1. sub-, infra-, lower, under

   ‎is- + ‎kevresek (“sequential”) → ‎iskevresek (“subsequent”)

   ‎is- + ‎poynt (“point”) → ‎ispoynt (“minimum”)

   ‎is- + ‎rudh (“red”) → ‎isrudh (“infrared”)

2. vice, deputy

   ‎is- + ‎breusydh (“referee”) → ‎isbreusydh (“assistant referee”)

   ‎is- + ‎lewydh (“president”) → ‎islewydh (“vice-president”)

is-

1. alternative form of iso-, before a vowel

• IPA^(key): /ɪs/

is-

1. alternative form of il-

• Used before the letter s. For details on usage, see the main lemma.

See is. Cognate with Cornish is-.

• IPA^(key): /ˌiːs/, /ɪs/

is-

1. lower, deputy, lieutenant, sub-, vice-, under-, by-

   Antonym: uwch-

   ‎is- + ‎arlywydd (“president”) → ‎is-arlywydd (“vice-president”)

   ‎is- + ‎deddf (“law”) → ‎is-ddeddf (“by-law”)

   ‎is- + ‎gorsaf (“station”) → ‎isorsaf (“substation”)

   ‎is- + ‎rhywogaeth (“species”) → ‎isrywogaeth (“subspecies”)

   ‎is- + ‎teitl (“title”) → ‎isteitl (“subtitle”)

• Triggers the soft mutation on the noun following.

• R. J. Thomas, G. A. Bevan, P. J. Donovan, A. Hawke, et al., editors (1950–present), “is-”, in Geiriadur Prifysgol Cymru Online (in Welsh), University of Wales Centre for Advanced Welsh & Celtic Studies