Minor Heat; 11th solar term
The 11th of the 24 solar terms (二十四節気), marking the beginning of the hottest period. Falls around July 7 in the modern calendar.
See also: 二十四節気
After Minor Heat, the real summer heat begins.
This year, Minor Heat falls on July 7th.
From Chinese solar term system. 小 (small, minor) + 暑 (heat), indicating the beginning of the hottest season.