Trojan horse - signifying a hidden danger; following ten years of a futile siege of the fortified city of Troy, the Greeks hid some of their warriors inside a wooden horse and pretended to leave in their ships, which were actually concealed out of sight. When the Trojans brought the huge wooden horse inside their walls in celebration, the soldiers hidden inside emerged under cover of darkness, opened the gates to the returned Greek army, and the Trojans were slaughtered.

Achilles' heel - meaning a single fatal vulnerability; the great Trojan War hero Achilles was shot in the heel, which was his only vulnerable spot - It proved deadly, even though he was supposed to be invulnerable. His mother Thetis held him by the heel when she dipped him in the River Styx in an attempt to render him immortal, keeping that part of his anatomy mortal.

Stentorian roar - Stentor was a herald of the Greeks at Troy, whose voice was as loud as that of fifty other men together. His name has become proverbial for any one who screams or shouts with an unusually loud voice.

Myrmidons - they were in the army of Achilles, a ferocious and warlike Thessalian people at the siege of Troy; the name today has come to mean a hired ruffian or unscrupulous subordinate.

Scylla and Charybdis - these were two horrible monsters, which would torment sailors who passed between them as they lurked on either side of a narrow sea passage. If sailors went one way, Scylla would devour them; the other way and Charybdis would make dinner of them! Being between Scylla and Charybdis is the idiom derived from the myth, meaning "having to choose between two evils", or "being between a rock and a hard place".

Siren voices - when the Trojan War hero Odysseus was sailing home following the war he and his shipmates had to navigate past an alluring collection of mermaids, which would sing so seductively that men would lose all interest in home and instead steer towards them, and to their death; Today it has come to mean any alluring or seductive temptation.

A Cassandra - (always wrongly used to mean prophet of doom; never actually used of somebody who is right). She correctly warned that the Trojans should not bring the Trojan Horse inside their walls, as it was a Greek trick, but she was disbelieved and the Trojans perished. Today the term has come to signify someone who is a prophet of doom, even though Cassandra was right!

A Mentor - Mentor was entrusted by Odysseus to safeguard his son and kingdom while he went off to fight in the Trojan War. When Odysseus returned home after twenty years, Mentor, who had tutored prince Telemachus, helped Odysseus defeat the pesky suitors that had set up camp inside his palace. The term mentor today refers to someone who acts as a teacher or spiritual advisor.