Plimsoll mark


: a load line or a set of load-line markings on an oceangoing cargo ship

called also Plimsoll line

Illustration of Plimsoll mark

Illustration of plimsoll mark
  • TF tropical freshwater mark
  • F freshwater mark
  • T tropical load line
  • S summer load line
  • W winter load line
  • WNA winter North Atlantic load line

Word History


Samuel Plimsoll †1898 English shipping reformer

First Known Use

1884, in the meaning defined above

Time Traveler
The first known use of Plimsoll mark was in 1884

Dictionary Entries Near Plimsoll mark

Cite this Entry

“Plimsoll mark.” Dictionary, Merriam-Webster, Accessed 20 May. 2024.

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