small box for holding loose tea.
A small container (often with lock and key) for tea, from catty, the Chinese or Malayan word for "pound", the quantity of tea originally contained in a caddy.
Tortoise shell or wooden box with a hinged lid and one or two compartments for holding tea. Tea was a valuable commodity during the 17th and 18th centuries, and, as evidence of this, many tea caddies from this period had locks.