Due esercizi da sedia per appiattire la pancia

What does “appiattire” mean in Italian?

Take the adjective piatto (“flat”), put a- in front and -ire behind, and you get appiattire, “to make flat.” Italian builds dozens of verbs this way, with the prefix and the ending arriving together — neither half works alone. Once you notice the shape, allungare (from lungo), accorciare (corto), ammorbidire (morbido) and alleggerire (leggero) stop being separate words to memorise.

Grammars call these verbi parasintetici. The a- doubles the following consonant (piatto → ap-piattire, corto → ac-corciare), and in- and s- build the same way: in + grande → ingrandire, s + bianco → sbiancare. The clip opens with the promise “vuoi appiattire la pancia?” and then uses a second one two lines later, when you ti avvicini — from vicino — to the back of the chair.