'pistil' originates from French, specifically the word 'pistil', where Latin 'pistillum' meant 'pestle'.

'pistil' changed from Latin 'pistillum' (meaning 'pestle') into Middle/Modern French 'pistil' and was adopted into English as 'pistil', the botanical sense arising by analogy to the pestle-like shape.

Initially it referred to a 'pestle' (a tool for grinding), but over time the term came to be applied to the pestle-shaped female part of a flower, giving the current botanical meaning.