roil
UK[rɔɪl]US[rɔɪl]
v
to make a liquid cloudy or muddy by stirring up sediment.
v
to make someone annoyed or agitated.
Etymology
the word 'roil' entered english in the late 16th century from middle french, where 'rouiller' meant to make liquid turbid. this french term is thought to be related to vulgar latin 'rubigulāre', a derivative of latin 'rubīgō' meaning 'rust', drawing a metaphorical link between the reddish color of rust and muddy water. the semantic evolution saw the core idea of 'disturbing to make cloudy' extend figuratively in english to describe the act of disturbing someone's emotions, leading to its modern meanings of agitating a liquid or a person's feelings. its journey reflects a common pattern where a concrete, physical action acquires an abstract, psychological sense.
Analysis
this word is a simplex form. it is likely of middle french origin, from the verb 'rouiller' meaning 'to make muddy', which itself is from old french 'roil', 'ruil' meaning 'muddy or turbid'. its functional role is as a single, indivisible lexical unit.
Examples
the passing boat began to roil the calm waters of the lake.
his constant criticisms were clearly starting to roil her.
don't shake the bottle; you'll roil the wine and disturb the sediment.