休眠
xiū mián · HSK 7
to be dormant
🐻💤 休 rest + 眠 sleep = resting-sleep, the deep dormancy of a hibernating animal or quiet volcano
休 is rest (as in 休息) and 眠 is sleep (as in 睡眠). Together: a prolonged rest-sleep state, so dormant in biology, inactive for a volcano, or hibernate mode on a computer.