青せい天てんせいてんFreq.FrequencyTop 100,000Meanings1nounblue sky; clear skyLiterary or formal word for a clear, blue sky. In everyday speech, 青空 (あおぞら) is more common.青せい天てんの下もと、桜さくらが満まん開かいだった。Under the blue sky, the cherry blossoms were in full bloom.