The Spanish word 'veintena' comes from combining the Spanish number 'veinte' (twenty) with the collective suffix '-ena'. The word 'veinte' itself derives from Latin 'viginti' meaning 'twenty'. When combined with the suffix '-ena', which is used to form collective numbers in Spanish, 'veintena' takes on the meaning of 'a group or score of twenty'.

The most obvious related Spanish word is 'veinte' (twenty), which is much more commonly used. Other Spanish words that use the same collective suffix '-ena' include 'docena' (dozen), 'decena' (group of ten), and 'centena' (group of hundred), following the same pattern of forming collective number words.

While English 'twenty' comes from a different Germanic root, there are some English words that share the Latin root 'viginti', though they're less common. These include 'vigesimal' (relating to the number twenty or based on counting by twenties) and 'vicennial' (occurring every twenty years). However, these are rather formal or technical terms in English.