The Spanish word 'sexta' meaning 'sixth (feminine)' comes from the Latin word 'sextus' meaning 'sixth', which itself was derived from the Latin word 'sex' meaning 'six'. This ordinal number formation follows a pattern common in Latin-derived languages, where number words are modified to create ordinal forms. The Spanish word maintains the feminine form of the Latin adjective, as indicated by the '-a' ending.

Some related Spanish words include 'seis' (six), 'sexto' (sixth - masculine form), and 'sexteto' (sextet). All these words share the same Latin root 'sex' meaning 'six'. The connection between these words is quite straightforward - they all relate to the concept of 'six' in different forms.

English speakers might recognize the connection to several English words that also derive from the Latin 'sex' (six), such as 'sextant' (a navigation instrument marked with a 60-degree arc), 'sextet' (a group of six), and 'sextuple' (sixfold). The word 'sixth' itself, while Germanic in origin rather than Latin, expresses the same concept. Understanding this common numerical origin can help English speakers remember the meaning of 'sexta'.