Contronyms (also spelled contranyms) are words that are their own opposites: For example, clip can mean to attach or to cut off. Contronyms are also known as janus words, antagonyms, and autoantonyms.

Here are some examples:

Bolt -to secure in place OR to flee quickly

Bound – going somewhere OR tied up and restricted from going anywhere

Cleave – to split apart OR to cling together

Consult – to offer advice OR to ask for it

Disciplined – well-behaved OR punished

Dust – to remove dust OR to sprinkle dust

Execute – to carry out (a task) OR to kill

Fast – quick OR firmly fixed and immobile

Finished – completed OR destroyed (as in “You’re finished!”)

Go – to proceed OR  to collapse (e.g., “The toaster is about to go.”)

Hold up – to support OR to delay

Lease – to rent out OR to rent from someone

Left – departed from OR remaining behind

Left off – started again where you stopped OR excluded

Oversight – careful management OR missed detail

Out -visible (e.g., stars are out) OR invisible (lights are out)

Pop – to suddenly appear OR disappear ( the balloon popped)

Resign – to quit a job OR to sign again (little different pronunciation)

Sanction – to permit OR to penalize

Screen -to display OR to hide (as in screening a movie vs. screening from the sun)

Seed – to plant seeds OR to remove seeds

Sick -Ill OR awesome (slang)

Stone -to pelt with stones OR to remove stones from (as in fruit)

Strike -to hit OR to miss (as in baseball)

Throw out – to discard OR to propose (e.g., an idea)

Trim – to decorate OR to remove excess

Weathered – withstood OR worn down by exposure

Wind up – to end OR to get started (as in winding up a toy)

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