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Mason-Dixon Line

Mason-Dixon Line proper noun: the boundary line between Pennsylvania and Maryland, as run (1764–1767) by Charles Mason and Jeremiah Dixon, that, before abolition, defined part of the northern boundary of states in which slavery was permitted.

Proper noun (1)

the Mason–Dixon Line

  1. (historical) The boundary line between Pennsylvania and Maryland, as run (1764–1767) by Charles Mason and Jeremiah Dixon, that, before abolition, defined part of the northern boundary of states in which slavery was permitted.
    • I am indebted to you for a topic to deny to the Pensylvania claim to a line 39 complete degrees from the equator. As an advocate I shall certainly insist on it; but I wish they would compromise by an extension of Mason & Dixon's line. — They do not agree to the temporary line proposed by our...1776, Thomas Jefferson, The Virginia Constitution (Letter to Edmund Pendleton), Philadelphia
    • The Virginia gentlemen offer to divide exactly the 40th degree with us, […] Perhaps we would be as well off with Mason and Dixon's line continued.1779, George Bryan, chapter 1779, in William Bradford Reed, editor, Life and Correspondence of Joseph Reed […] , volume 2, Philadelphia: Lindsay and Blakiston, published 1847, George Bryan to...
  2. The boundary between the free and slave states at the time of the American Civil War, or between states with different segregationist policies in the Jim Crow era.
    • […] and he tell'd me Georgia would go for me, arter^([sic]) the Gineral^([sic]), as soon as any north of mason and dickson^([sic]).1833, Charles Augustus Davis, “Letter III […] ”, in Letters of Jack Downing, Major […] , New-York: Harper & brothers, published 1834, page 36
    • The epistles are not dated far apart; and in the second, the writer, who dwelleth near ‘Mason and Dixon,’ descants upon the awful climate hereabout in the summer months.1843, Charles Fenno Hoffman, John Holmes Agnew, “Editor's Table”, in The Knickerbocker; Or, New-York Monthly Magazine, volume 22, New-York: John Allen, page 185

Proper noun (2) capitalized: Mason-Dixon line

Mason-Dixon line

  1. Alternative letter-case form of Mason-Dixon Line.

Forms of Mason-Dixon Line

alternative formMason-Dixon line
alternative formMason and Dixon line
alternative formMason's and Dixon's line

Origin of Mason-Dixon Line

Named after English astronomers Charles Mason (1728–1786) and Jeremiah Dixon (1733–1779).

Words formed from Mason-Dixon Line

Questions about Mason-Dixon Line

What does Mason-Dixon Line mean?
Mason-Dixon Line means the boundary line between Pennsylvania and Maryland, as run (1764–1767) by Charles Mason and Jeremiah Dixon, that, before abolition, defined part of the northern boundary of states in which slavery was permitted.
What part of speech is Mason-Dixon Line?
Mason-Dixon Line is a proper noun.

Words near Mason-Dixon Line in the dictionary

  1. mason wasps
  2. mason worm
  3. mason worms
  4. Mason's and Dixon's line
  5. Mason's Island
  6. Mason-Dixon Line
  7. masonary
  8. masoncraft
  9. masoncrafts
  10. masondom
  11. Masone

Source and license

Adapted from Wiktionary: Mason-Dixon Line (page history and authors); Mason-Dixon line (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

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