take the plunge

Meaning: to commit to something risky; to make a decisive move.

Language: English

Literally: to take the plunge

Category: Nature

Origin: The force of the phrase comes from a specific property of diving rather than from water generally: a dive is the rare physical act that cannot be recalled once begun. A person can stand at the edge hesitating for as long as they like, but the instant they commit, gravity finishes the motion whether they have changed their mind or not — which makes it an exact figure for a decision that forecloses retreat. Figurative use is established in English through the 1800s, and over the twentieth century the phrase attached itself so firmly to getting married that this is now its most common application, though it works equally well for any irreversible commitment approached after a long period of hesitation.