Literal translation
that set fire to the tow
Meaning
that lit the fuse
Explanation
The expression describes an event that suddenly triggers anger, a quarrel, or a crisis. Literally, acò metè fiò is estoumpo translates as that set fire to the tow: tow, a coarse plant fiber drawn from flax or hemp, traditionally served as tinder or wick, catching instantly at the slightest contact with an ember or a spark, unlike denser wood that would take longer to ignite. The image thus stresses the speed and violence with which a latent tension can burst into the open as soon as even a minor trigger reaches it. The register is common, used to comment, often in hindsight, on the precise cause of a collective outburst or a quarrel that escalated quickly. It matches the French mettre le feu aux poudres or light the fuse, sharing the same logic of a sudden blaze set off by a seemingly harmless incident.