mouthpiece

Etymology

It is a compound from English mouth + piece.^[2][3][4][5] Mouth is from Old English mūþ,^[3] and piece is from Old French piece (“piece, bit, portion”).^[3]

Earliest recorded meaning

The part of a musical instrument, pipe or other device that is placed between or against the lips: 1673, in J. Phillips's Maronides.^[2][6] Etymonline dates the word to the 1680s, of a casting fitted on the open end of a pipe.^[3]

Semantic evolution

Horsemen used it from 1728 for the part of a bit that crosses the horse's mouth.^[2] From 1790 it was also a covering for the mouth, later a gumshield,^[2] the speaking part of a telephone followed in 1877.^[2] Something forming an aperture is recorded from 1683.^[2] The figurative sense, a person, organization or newspaper that speaks for others, is dated by the OED to 1776^[2] and by Etymonline to 1805.^[3] In criminals' slang it came to mean a lawyer, especially a defence counsel; the OED and Etymonline date this to 1857,^[2][3] and Green's Dictionary of Slang finds it in a Sydney paper in 1846.^[7] The colloquial, often humorous use for the mouth itself is rare, from 1738 in Swift.^[2]

Timeline

• 1673 – the part of an instrument or pipe placed against the lips.^[2][6] Etymonline dates the word to the 1680s.^[3]
• 1683 – something forming an aperture.^[2]
• 1728 – the part of a horse's bit that crosses the mouth.^[2]
• 1738 – humorously, the mouth.^[2]
• 1776 – a person or publication that speaks for others.^[2] Etymonline dates this sense to 1805.^[3]
• 1790 – a covering for the mouth; later a gumshield.^[2]
• 1846 – a lawyer, in slang.^[7] The OED's first record is from 1857.^[2]
• 1877 – the part of a telephone into which one speaks.^[2]

Meanings

Noun

1. The part of a wind instrument into which the player blows.^[8][6][9][2]
2. The part of a telephone or similar device into which a person speaks.^[8][9][2]
3. A part of a pipe, respirator or other device that goes in or against the mouth; also a cigarette or cigar holder.^[6][2]
4. The part of a container or pipe that forms its opening.^[8][6][2]
5. A gumshield or other protective guard for the teeth, worn especially by boxers.^[8][9][2]
6. The part of a horse's bit that crosses the mouth.^[6][2]
7. A person, organization or publication that expresses the views of another or others; a spokesperson: The magazine became the mouthpiece of the opposition.^[8][9][2]
8. (slang) A lawyer, especially a defence counsel.^[9][2][7]

Related words

• mouth
• piece

References

1. ^ Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f g h i j k l m n o p q r s t u v w x y Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
3. ^ a b c d e f g h Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
4. ^ Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
5. ^ Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
6. ^ a b c d e f Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
7. ^ a b c Green, Jonathon (2010), Green's Dictionary of Slang, London: Chambers; digital ed. 2016–, https://greensdictofslang.com
8. ^ a b c d e Collins English Dictionary (2023), Glasgow: HarperCollins
9. ^ a b c d e The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt