Tereré or terere (of Guaraní origin) is an infusion of yerba mate (botanical name Ilex paraguariensis), similar to mate but prepared with cold water and ice rather than with hot water, and in a slightly larger vessel.

This infusion has its roots in Pre-Columbian America, which established itself as traditional during the time of Governorate of Paraguay. The Guaraní people call this infusion ka'ay, where ka'a means herb and y means water.

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