The Spanish word 'cabrilla' comes from combining the Spanish word 'cabra' (meaning 'goat') with the diminutive suffix '-illa'. The word 'cabra' itself derives from the Latin word 'capra', meaning 'female goat'. So 'cabrilla' literally means 'little goat' or 'small goat'.

This is a classic example of Spanish word formation using the diminutive suffix '-illa', which is commonly added to nouns to indicate smallness or endearment.

The most obvious related Spanish word is 'cabra' (goat), which is a more common and simpler word that Spanish learners might encounter first. Other related words in the same word family include 'cabrón' (male goat, though this has taken on vulgar connotations), 'cabrero' (goatherd), and 'cabrería' (goat farm).

While English doesn't have many common words directly related to the Latin 'capra', there are some specialized terms that share this ancestry. For example, the word 'caprine' meaning 'goat-like' or 'relating to goats' comes from the same Latin root. The astrological sign 'Capricorn' (literally 'goat horn') also contains this root.