A device or person that infuses; specifically, a container designed to steep tea, herbs, or flavoring in liquid.
From 'infuse' (to pour or soak into) plus '-er' (a device that does something). The noun form grew as kitchen tools became specialized in the modern era.
Infusers seem modern, but they're basically reinventing what people have done for millennia—the ancient world made infusions in clay pots, but calling a mesh ball an 'infuser' makes it feel like technology solved tea.
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