Tool that it takes two to operate

• A large two-handed saw formerly used to cut logs into planks
• Tool for a pair of timber cutters
• Two-person cutter
• Log cutter for two
• Lumberjack's tool
• Two-person tool
• Cutting tool handled by a couple of people

Wiktionary Word definitions in Wiktionary
n. A saw worked by two people, one standing on the log and the other beneath it, often in a pit.

The Collaborative International Dictionary Word definitions in The Collaborative International Dictionary
pitsaw \pit"saw\ n. A large two-handed saw formerly used to cut logs into planks; one man stood above the log and the other in a pit below.