undissolved

/ˌʌndɪˈzɑlvd/
adjective
  1. Not having been mixed into a liquid to form a solution; remaining as solid particles.
    • After stirring the sugar into the cold tea, some undissolved crystals remained at the bottom of the glass.
    • The recipe said to heat the mixture until no undissolved powder was visible.
    • He strained the undissolved coffee grounds out of the cup before drinking.
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