Wiktionary
achilles' heels
n. (Achilles' heel lang=en nodot=1) ((alternative spelling of Achilles heels lang=en nocap=1 nodot=1)).
Usage examples of "achilles' heels".
She watched a fresh salvo claw at Achilles' heels, and her smile was thin and cold.
Trouble is, Rebecca's stings are aimed so subtly at one's Achilles' heels, like Gulf War missiles going 'Fzzzzzz whoossssh' through Baghdad hotel corridors, that never see them coming.
He'd been working for McKinsey, systematically undermining their GMT-based clients with plausibly terrible advice, creating Achilles' heels that their East-coast competitors could exploit.