from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A machine with three pulleys which act together to raise great weights.
from the GNU version of the Collaborative International Dictionary of English
- n. A machine with three pulleys which act together for raising great weights.
from The Century Dictionary and Cyclopedia
- n. A machine with three pulleys acting in connection with each other, for raising great weights.
From Ancient Greek "drawn threefold". (Wiktionary)
This kind of machinery, revolving with three sheaves, is called a trispast.