A checked tone, commonly known by the Chinese calque entering tone, is one of the four syllable types in the phonology of Middle Chinese. Although usually translated as "tone", a checked tone is not a tone in the western phonetic sense but rather a type of syllable that ends in a stop consonant or a glottal stop. Separating the checked tone allows -p, -t, and -k to be treated as allophones of -m, -n, and -ng, respectively, since they are in complementary distribution. Stops appear only in the checked tone, and nasals appear only in the other tones. Because of the origin of tone in Chinese, the number of tones found in such syllables is smaller than the number of tones in other syllables. Chinese phonetics have traditionally counted them separately.
Final voiceless stops and therefore the checked "tones" have disappeared from most Mandarin dialects, spoken in northern and southwestern China, but have been preserved in southeastern Chinese branches like Nanjing Mandarin, Yue, Min, and Hakka.