The Spanish word 'mío' meaning 'my' or 'mine' comes directly from the Latin word 'meus', which had the same meaning. This is a straightforward inheritance from Latin to Spanish, with the Latin 'meus' evolving phonetically to become 'mío' in Spanish while maintaining its function as a possessive pronoun.

Some related Spanish words include 'mi' (my), which is the shorter, unstressed form of 'mío' used before nouns. While 'mío' is used as a predicate ('es mío' - it is mine) or after nouns for emphasis ('hijo mío' - my son), 'mi' is the more common form used in everyday speech ('mi casa' - my house).

While English 'my' and 'mine' might look similar to 'mío', they actually come from Germanic roots rather than Latin. However, English does have some words related to 'mío' through Latin, such as 'me' and 'my' in words like 'myself'. The Latin influence can also be seen in words like 'memorial' and 'memory', which relate to things belonging to or associated with oneself, though these connections are more distant.