The Spanish word 'bombita' meaning 'small bomb' comes from the Spanish word 'bomba' (bomb) with the diminutive suffix '-ita'. The word 'bomba' traces back to Latin 'bombus', meaning 'buzzing' or 'deep sound', which itself comes from Ancient Greek 'βόμβος' (bombos), meaning 'resonant sound' or 'buzzing'. The evolution of meaning from a sound-based word to an explosive device likely came from the booming sound that explosions make.

Some related Spanish words that might be more familiar include 'bomba' (bomb), 'bombón' (chocolate, candy - another diminutive form but with a different suffix), and 'bombardear' (to bomb, to bombard). All these words share the same explosive or impact-related theme from the root 'bomba'.

English speakers might recognize the connection to words like 'bomb', 'bombard', and 'bombardment'. These words share the same Greek and Latin ancestry as the Spanish 'bombita'. The English word 'boom' (meaning a loud, deep sound) is also conceptually related, though it has a different etymological origin.