the.com/aneurysm

means A weakened, bulging patch in an artery wall that swells like a thin spot in a tire — dangerous because it can rupture.

from From Greek 'aneurysma,' meaning 'a widening' or 'dilation,' built from 'ana-' (up) plus 'eurys' (wide, broad). The same 'eurys' root shows up in names like Eurydice. Greek physicians used the word for exactly this — a vessel stretched wider than it should be — and the term passed into Latin medical writing and then into English largely unchanged, still describing the same ominous swelling.