the.com/secret weapon

The person or trick you downplay in meetings but pray never leaves.

means A hidden advantage, skill, or resource held in reserve and deployed to win when it matters most.

from A straightforward compound of 'secret' (Latin secretus, 'set apart, hidden,' from secernere, 'to separate') and 'weapon' (Old English wæpn). The literal military sense — an undisclosed new arm that could win a war before the enemy could counter it — became common talk in the 20th century, especially around wartime technology, and from there leapt happily into sports, business, and gossip about who's actually doing the work.

irony
loses power the moment you announce it
often
an underestimated intern or overlooked spreadsheet
military origin
WWII propaganda term for unproven superweapons
best used
sparingly, then everyone wants their own
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