The Spanish word 'perico' (meaning 'small parrot') has an interesting etymology that traces back to the Greek name 'Petros' (Πέτρος), meaning 'stone' or 'rock'. This Greek word evolved into the Latin name 'Petrus' (Peter), which then developed into the Spanish variant 'Pero' (a form of Pedro). The word 'perico' was formed by adding the Spanish diminutive suffix '-ico' to 'Pero'.

The connection between the name Peter and parrots might seem strange, but it's similar to how other birds have received names from human names (like 'robin' or 'martin'). The diminutive form suggests endearment, possibly reflecting how these birds were kept as pets.

The most obvious related Spanish word is 'Pedro', which is the standard Spanish form of Peter. You might also encounter 'Pero', though this older variant is less common today. The diminutive suffix '-ico' is still commonly used in Spanish, especially in certain regions, to form affectionate diminutives of names and words.

The English name 'Peter' shares the same Greek origin as 'perico', both ultimately coming from 'Petros' meaning 'rock' or 'stone'. The word 'petroleum' (literally 'rock oil') also contains this same root 'petr-'. While these words have very different meanings today, they all trace back to the same ancient Greek word for 'rock'.