Definition
To introduce (someone) to a new situation without adequate preparation.
Origins
From allusion to an actual swimming pool with a shallow end and deep end. In the shallow end, a person can stand on the bottom. In the deep end, the water is too deep to do this, so a person must be able to swim or at least tread water or drown.
See Also
- hit the ground running
- sink or swim
- in at the deep end