The Spanish interjection 'pucha' is a euphemistic variant of the Spanish word 'puta' (meaning 'prostitute'). It's used as a milder expletive or expression of frustration, similar to how English speakers might say 'darn' instead of stronger curse words. The modification of 'puta' to 'pucha' softens the word by changing the 't' to 'ch', making it more socially acceptable in casual conversation.

The most obvious related Spanish word is 'puta', though it's important to note that this is considered a strong profanity in Spanish. 'Pucha' was specifically created as a less offensive alternative that could be used in polite company.

While there aren't direct English cognates, the transformation of 'pucha' from 'puta' follows a similar pattern to how English creates euphemisms by modifying taboo words, like 'darn' for 'damn' or 'heck' for 'hell'.