False friend ES sounds like CS
camisa
ES [kaˈmisa] · sounds like Czech kamizolka
Czech ear hears kamizolka — a waistcoat / vest Actually camisa — a shirt
Spanish camisa is simply a shirt. To my Czech ear it first resembled kamizolka - a waistcoat or a little vest - so the spidey sense was almost right, but not quite.
They are genuinely related, which is the trap. Both go back to Latin camisia, “shirt.” The Czech word took a little scenic route from Italian camiciola to French camisole to Czech kamizolka and picked up a different garment along the way. One Latin shirt, two wardrobes.
Straight ES camisa = shirt
CS kamizolka = waistcoat / vest
shared ancestor: Latin camisia, “shirt”
Why it happens
The same shape as divertido: as far as I can find, a real etymological link that misleads. The dictionaries I checked trace both to Latin camisia (“shirt”), the Czech apparently arriving via Italian camiciola and French camisole. Same ancestor, different garment today.