chapter 2.4.2 a pronouncing dictionary

[Chen-Xuying]

"minimally contrasting sets of words" is a phonological term, deriving from "the minimal contrast pair（最小对比对）", according to which, the term here should not be translated as "最小受限集合", but "最小对比集合".
A minimal contrast pair is a pair of words like "pit" and "pet", providing evidence that /i/ and /e/ are independent phonemes in English phonology.