interjection

noun2

1. •
   An exclamation or filled pause; a word or phrase with no particular grammatical relation to a sentence, often an expression of emotion.

   • 322. The parts of speech which are neither declined nor conjugated, are called by the general name of particles. 323. They are adverbs, prepositions, conjunctions, and interjections. — 1844
2. •
   An interruption; something interjected