Meanings
nounjack block (plural jack blocks)
plural jack blocks
- nauticalA block fixed in the topgallant or royal rigging, used for raising and lowering light masts and spars.
Cite this entry
APA
jack block. (n.d.). In WatkinsX Dictionary. Retrieved November 2, 2026, from https://dictionary.watkinsx.com/word/jack%20block
MLA
“jack block.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/jack%20block. Accessed November 2, 2026.
Chicago
WatkinsX Dictionary, s.v. “jack block,” accessed November 2, 2026, https://dictionary.watkinsx.com/word/jack%20block.
Source: jack block on Wiktionary, CC BY-SA 4.0.