The Spanish word 'matamoscas' (meaning 'flyswatter') is a compound word formed from two parts: 'mata-' (from the verb 'matar', meaning 'to kill') and 'moscas' (from 'mosca', meaning 'fly'). The verb 'matar' comes from the Latin word 'mactare', which originally meant 'to sacrifice' but evolved to mean 'to kill' in Spanish. The word 'mosca' comes directly from the Latin word 'musca', meaning 'fly'. When combined, 'matamoscas' literally means 'fly-killer', which perfectly describes the function of a flyswatter.

Some simpler Spanish words that share this etymology are 'matar' (to kill) and 'mosca' (fly). These are both very common words that you might encounter early in your Spanish learning journey. You might also see 'matador' (the bullfighter who kills the bull), which comes from the same verb 'matar'.

While English 'kill' and 'swatter' aren't related to 'matamoscas', we do have some words that share ancestry with the 'mosca' part. The English word 'mosquito' (which Spanish also uses) is actually a diminutive form meaning 'little fly', derived from the same Latin root 'musca'. Similarly, 'muscoid' (fly-like) and 'muscarine' (a toxic compound first isolated from a species of fly agaric mushroom) are scientific terms that come from this Latin root.