railroad jack

noun

1

: a portable jack used for heavy lifting

2

a

: a 4-screw or 6-screw hoist operated by electric motors for lifting locomotives off their wheels while they are undergoing repairs

b

: a hydraulic lift device operated either by hand lever or motor

Love words?

You must — there are over 200,000 words in our free online dictionary, but you are looking for one that’s only in the Merriam-Webster Unabridged Dictionary.

Start your free trial today and get unlimited access to America's largest dictionary, with:

• More than 250,000 words that aren't in our free dictionary
• Expanded definitions, etymologies, and usage notes
• Advanced search features
• Ad free!