窺伺 [窥－]

Jyutping kwai1 zi6
Pinyin kuī sì

Definitions (CC-CEDICT)

to spy upon
to lie in wait for (an opportunity)

Definitions (Wiktionary)

verb, derogatory, often
to lie and wait for; to be on watch for
(syn.) 偵伺, 侦伺

Definitions (Kaifangcidian)

（沒有對應漢語詞彙）