• (RP) enPR: kŏg, IPA: /kɒɡ/
• (America) enPR: kôg, IPA: /kɔɡ/
• (cot-caught) enPR: kŏg, IPA: /kɑɡ/

From Middle English cogge, from Old Norse (compare Norwegian kugg, Swedish kugg), from Proto-Germanic *kuggō (compare Dutch kogge, German Kock), from Proto-Indo-European *gugā (compare Lithuanian gugà), from *gēw- ("to bend, arch").

The meaning of “cog” in carpentry derives from association with a tooth on a cogwheel.

cog (plural cogs)

1. A tooth on a gear.
2. A gear; a cogwheel.
3. An unimportant individual in a greater system.
   • 1976, Norman Denny (English translation), Victor Hugo (original French), Les Misérables

     ‘There are twenty-five of us, but they don’t reckon I’m worth anything. I’m just a cog in the machine.’

   • 1988, David Mamet, Speed-the-Plow

     Your boss tells you “take initiative,” you best guess right—and you do, then you get no credit. Day-in, … smiling, smiling, just a cog.

4. (carpentry) A projection or tenon at the end of a beam designed to fit into a matching opening of another piece of wood to form a joint.
5. (mining) One of the rough pillars of stone or coal left to support the roof of a mine.

• French: dent
• German: Zahn
• Portuguese: dente
• Russian: зубе́ц
• Spanish: diente

• French: pion
• German: Rädchen
• Italian: rotellina
• Russian: ви́нтик

• German: Zapfen

cog (cogs, present participle cogging; simple past and past participle cogged)

1. To furnish with a cog or cogs.
2. (intransitive) Of an electric motor or generator, to snap preferentially to certain positions when not energized.

From Middle English cogge, from Middle Dutch kogge, cogghe (modern kogge), from Proto-Germanic *kuggō (compare German Kock, Norwegian kugg), from Proto-Indo-European *gugā (compare Lithuanian gugà), from *gēw- ("to bend, arch").

cog (plural cogs)

1. (historical) A clinker-built, flat-bottomed, square-rigged mediaeval ship of burden, or war with a round, bulky hull and a single mast, typically 15 to 25 meters in length.
   • 1952, C. S. Lewis, The Voyage of the Dawn Treader:

     The name of the ship was Dawn Treader. She was only a little bit of a thing compared with one of our ships, or even with the cogs, dromonds, carracks and galleons which Narnia had owned when Lucy and Edmund had reigned there under Peter as the High King, for nearly all navigation had died out in the reigns of Caspian's ancestors.

2. (by extension) A small fishing boat.

• German: Kogge
• Russian: когг
• Spanish: coca

cog (plural cogs)

1. A trick or deception; a falsehood.

cog (cogs, present participle cogging; simple past and past participle cogged)

1. To load (a die) so that it can be used to cheat.
2. To cheat; to play or gamble fraudulently.
   • 1726, Jonathan Swift (debated), Molly Mog

     For guineas in other men's breeches, / Your gamesters will palm and will cog.

3. To seduce, or draw away, by adulation, artifice, or falsehood; to wheedle; to cozen; to cheat.
   • c. 1608–1609 (date written), William Shakespeare, “The Tragedy of Coriolanus”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, →OCLC ↗, [Act III, scene ii]:

     I'll mountebank their loves,
     Cog their hearts from them.

4. To plagiarize.
5. To obtrude or thrust in, by falsehood or deception; to palm off.

   to cog in a word

   • October 3, 1718, John Dennis, letter to S. T. , Esq; On the Deceitfulness of Rumour

     Fustian tragedies […] have […] been cogg'd upon the town for Master-pieces.

cog (plural cogs)

1. Alternative form of cogue

cog (plural cogs)

1. Init of center of gravity

   Synonyms: C.O.G., C. O. G., CoG, C.o.G., C. o. G., CG, C.G., C. G., cog, c.o.g., c. o. g., cg, c.g., c. g.

   Coordinate terms: COM/CoM/CM, COP/CoP/CP, COI/CoI/CI, COB/CoB/CB

2. (nautical) Abbreviation of course over ground

   Coordinate term: SOG

1. Initialism of Church of God: numerous, mostly unrelated Christian denominations.