[----]

Jyutping sing1 sing1 soeng1 sik1
Pinyin xīng xīng xiāng xí

Definitions (Wiktionary)
  1. phrase, idiomatic
    to have a friendship based on intellectual compatibility

[----]

Jyutping sing1 sing1 soeng1 sik1
Pinyin xīng xīng xiāng xī

Definitions (CC-CEDICT)
  1. see 惺惺惜惺惺[xing1 xing1 xi1 xing1 xing1]
Definitions (粵典–words.hk)
  1. 動詞
    才能​相​當​嘅​人​愛​惜​彼此​嘅​才能​,​彼此​支持
    rapport between people with extraordinary abilities
Definitions (Wiktionary)
  1. phrase, idiomatic
    to have a friendship based on intellectual compatibility