dunno

Written form of don't know, which is a reduction of do not know or does not know.

• (Received Pronunciation) IPA^(key): /ˈdʌnəʊ/, /dəˈnəʊ/
• (General American) IPA^(key): /dəˈnoʊ/; (after a stressed pronoun) /dn̩oʊ/ (e.g. I dunno is /ˈaɪdn̩oʊ/)

dunno

1. Eye dialect spelling of do not know; eye dialect spelling of does not know.

   I dunno the answers to any of those questions, and you dunno and he dunno either.

   "Where'd he go?" / "Dunno."

This is one of the only verb forms in English that regularly does not require a pronoun. When the pronoun is not given, it is assumed to be I; all other pronouns must be given. It is never mandatory to drop I, although it is most common to do so when dunno is the only word in the sentence.

dunno (plural dunnos)

1. An utterance of the word dunno.

• “dunno” (US) / “dunno” (UK) in Oxford Dictionaries, Oxford University Press.