The Spanish word 'igual' (meaning 'equal') comes from the Latin word 'aequalis', meaning 'equal' or 'uniform'. 'Aequalis' itself was formed by combining the Latin root 'aequus' (meaning 'level, even, just') with the relational suffix '-alis'. Over time, as Latin evolved into Spanish, 'aequalis' transformed into 'igual' through regular sound changes, while maintaining its core meaning of equality or sameness.

Some common Spanish phrases using 'igual' include 'igualito' (exactly the same), 'igualarse' (to equal oneself to), and 'igualitario' (egalitarian). The word appears frequently in everyday expressions like 'da igual' (it doesn't matter) and 'al igual que' (just like, similarly to).

English speakers might recognize the connection between 'igual' and words like 'equal', 'equality', and 'equalize', which all come from the same Latin root 'aequalis'. Another related English word is 'equitable' (fair or impartial), which traces back to the Latin 'aequus'. Understanding this connection can help English speakers remember that 'igual' means 'equal' in Spanish.