The story
Suggesting that the tea is dense enough for a mouse to walk across without sinking.
Etymology from Wiktionary, CC BY-SA 4.0.
strong enough to trot a mouse on
Today it means: Of tea or coffee etc.: made very strong. Full definition →
Today it means: Of tea or coffee etc.: made very strong. Full definition →
Suggesting that the tea is dense enough for a mouse to walk across without sinking.
Etymology from Wiktionary, CC BY-SA 4.0.