The Spanish word 'rojito' comes from combining the Spanish adjective 'rojo' (meaning 'red') with the diminutive suffix '-ito'. The base word 'rojo' itself derives from the Latin word 'russus', meaning 'red'. The diminutive suffix '-ito' adds the meaning of 'little' or indicates a lesser degree of the quality, so 'rojito' means 'reddish' or 'little red'.

This is a classic example of Spanish word formation where a diminutive suffix modifies the meaning of the base word to express smallness, endearment, or in this case, a lighter shade of the color.

The most obvious related Spanish word is 'rojo' (red), which is the base word of 'rojito'. Other common related words include 'rojizo' (reddish), 'enrojecer' (to redden), and 'rojear' (to show a red color). All these words share the same Latin root 'russus' and form part of the Spanish color vocabulary family.

While English 'red' is not directly related to Spanish 'rojito', there are some English words that share the Latin root 'russus'. The most notable is 'russet', which refers to a reddish-brown color and is particularly used to describe certain types of apples and potatoes. The word 'rouge', borrowed from French but commonly used in English for red makeup, is also distantly related, as French 'rouge' comes from the same Latin root as Spanish 'rojo'.