轻声字 (輕聲字) qīngshēngzì

qīngshēngzì noun a weakly stressed syllable; a neutral tone
Domain: Linguistics 语言学 , Subdomain: Phonetics
Notes: A syllable that is reduced in tone range and short in duration and is commonly the second syllable in two syllable word (Norman 1988, pp. 148-149).