lei2

lei2 is the tone-number representation of the Mandarin syllable lei in pinyin, indicating the second tone. In pinyin, tone numbers are an alternative to diacritic marks; lei2 corresponds to léi, a rising pitch. The second tone is typically described as starting mid and gliding upward.

Phonologically, lei consists of the initial l and the final ei, and is pronounced as a rising diphthong [lei] in IPA. The same syllable can carry different meanings depending on the Chinese character and context.

In Chinese, lei as a syllable appears in several common words and proper nouns. The character 雷, meaning “thunder,” is read léi, which aligns with lei2 in tone-number notation. The surname Lei is written Léi in pinyin and is one of the more prominent uses of this syllable. Other words include 雷电 léi diàn “thunder and lightning” and 雷声 léi shēng “the sound of thunder.” The precise meaning of lei2 depends on the accompanying character.

In education and digital input, lei2 is frequently used to indicate the second tone without diacritics, aiding learners and input-method software. It also appears in linguistic discussions of Mandarin tone patterns and in dictionaries that employ tone-number notation for compactness.