The Spanish word 'ingle' comes directly from the Latin word 'inguen', which meant 'groin'. This is a straightforward etymology where both the meaning and form remained quite stable as the word evolved from Latin to Spanish. The main change was the simplification of the word structure, where the final '-n' was dropped, a common phenomenon in the evolution from Latin to Spanish words.

There aren't many common Spanish words that are etymologically related to 'ingle', as this anatomical term stands relatively isolated in modern Spanish vocabulary.

While English doesn't have any common words directly related to 'ingle', the medical term 'inguinal' (relating to the groin) comes from the same Latin root 'inguen'. You might encounter this word in medical contexts, such as 'inguinal hernia' or 'inguinal canal'.