'pistilless' originates from the word 'pistil,' which comes from the Latin word 'pistillum,' meaning 'pestle.' The suffix '-less' is used to indicate the absence of something.

'pistil' changed from the Latin word 'pistillum' and eventually became the modern English word 'pistil.' The suffix '-less' was added to form 'pistilless.'

Initially, 'pistil' referred to the pestle of a mortar, but over time it evolved to refer to the female reproductive part of a flower. 'Pistilless' indicates the absence of this part.