'linearize' originates from English usage combining 'linear' and the suffix '-ize' (from Greek '-izein' via Latin/French), where 'linear' comes from Latin 'linearis' meaning 'of or pertaining to a line' and '-ize' meant 'to make or to render'.

'linearize' was formed in Modern English by adding the productive verbal suffix '-ize' to the adjective 'linear' (from Middle English 'linear', from Latin 'linearis' < 'linea'), producing the verb 'linearize'.

Initially it simply meant 'to make linear' or 'to render into a line-related form'; over time, especially in mathematics and engineering, it also came to mean 'to approximate a nonlinear object by a linear one' (a specialized technical sense).