teacup
A small, delicate cup used for drinking tea.
A teacup is a small cup designed specifically for drinking tea. Unlike a mug, which has straight sides and holds more liquid, a teacup often has a delicate, rounded shape with a handle and usually sits on a matching saucer (a small plate). Teacups are typically made of fine china or porcelain and hold just a few ounces of tea.
The phrase tempest in a teacup describes when people get extremely upset about something that doesn't really matter much. If two friends have a huge argument about whose turn it is to erase the whiteboard, that's a tempest in a teacup: a tiny problem blown way out of proportion, like imagining a dangerous storm contained in something as small as a teacup.
You might also hear someone described as a teacup dog or teacup pig, meaning an animal bred to be unusually tiny. These animals might fit in the palm of your hand when they're young.