from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. a pipe to drain or let off water
from the GNU version of the Collaborative International Dictionary of English
- n. A pipe to let off water.
from The Century Dictionary and Cyclopedia
- n. A pipe laid at the level of the bottom of a canal for letting off the water.
From off- + let (Wiktionary)
First, the water might be run off by a descending pipe, if an offlet could be got at the depth of thirty-five or thirty-six feet, and any air might be extracted by a small pump.