'avocado' originates from Spanish, specifically the word 'aguacate', which comes from Nahuatl 'āhuacatl', where 'āhuacatl' meant 'testicle' (a reference to the fruit's shape).

'āhuacatl' (Nahuatl) became 'aguacate' in Spanish and was adopted into English as 'avocado' in the 17th–18th centuries; an alternate English name used historically was 'alligator pear'.

Initially, the Nahuatl word referred to 'testicle' (alluding to shape); over time it became the name for the fruit in Spanish and English and lost the original anatomical sense in common usage.