Answer: brei

AnswerCrossword Clue
BREIMatzo ... (egg dish)
BREITissue suspension
BREICulture tissue
BREICulture for some viruses
breisuspension of finely divided tissue in an isotonic medium, used chiefly as a culture for certain viruses
brei(South Africa) to pronounce r sound at the back of the throat also BREY