because they look like flying mice [Danish: flagermus, German: Fledermaus, Luxembourgish: Fliedermaus, Swedish: fladdermus]
because they look like half mice and half owl [French: chauve-souris]
because they look like half mice and it’s not 100% clear what the other half is [Ladin: utschè-mezmieur, Catalan: rat-penat, Lombard: mezzarat]
because apparently they make a flap flap noise [English: bat]
because they’ve got badass leather wings [Gaelic: sciathàn leathair, Old Norse: leðrblaka]
because they look like cute nocturnal butterflies [Maltese: farflett il-lejl]
because they’re probably, like, blind mice [Serbo-croatian: sismis, Portugese: morcego, Spanish: murcíelago, Arabic: khaffash]
because they fly at night [Italian: pipistrello, Slovenian: netopir, Polish: nietoperz, Greek: nykterides, Farsi: shab parreh]
Originally posted by daily-batty-dose
So bat literally means flapper. You’re welcome.
This, my friends, this is true etymology. Explaining why something is named the way it is, finding patterns and principles of meaning, not just tracing a word’s form back through time (which, admittedly, is oftentimes a prerequisite for exploring the former).