The Spanish word 'horchata' traces its origins back to the Latin word 'hordeum', meaning 'barley'. This Latin word evolved into the Italian 'orzo' (also meaning 'barley'). In Italian, when combined with the suffix '-ata' meaning 'product made from', it formed 'orzata', literally meaning 'barley drink'. The word then passed through Valencian, where it became 'orxata', before finally entering Spanish as 'horchata'.

While the original drink was made from barley, modern horchata in Spanish-speaking countries is often made from different ingredients like rice, almonds, or tiger nuts, though it retained its historical name derived from barley.

There aren't many common Spanish words directly related to 'horchata' since it entered Spanish as a complete borrowed term from Valencian. The word stands somewhat isolated in Spanish vocabulary, making it a unique term specifically associated with the beverage.

English speakers might recognize a connection to the word 'orzo', which came from the same Latin root 'hordeum'. While horchata became a name for a sweet drink, orzo in English refers to rice-shaped pasta that was traditionally made from barley flour. Both words preserve a connection to their barley-related origins, though they've come to refer to very different food products.