forge (n.)

late 14c., "a smithy," from Old French forge "forge, smithy" (12c.), earlier faverge, from Latin fabrica "workshop, smith's shop," hence also "a trade, an industry;" also "a skillful production, a crafty device," from faber (genitive fabri) "workman in hard materials, smith" (see fabric). As the heating apparatus itself (a furnace fitted with a bellows), from late 15c. Forge-water (1725), in which heated iron has been dipped, was used popularly as a medicine in 18c.

forge (v.1)

early 14c., "to counterfeit" (a letter, document, etc.), from Old French forgier "to forge, work (metal); shape, fashion; build, construct; falsify" (12c., Modern French forger), from Latin fabricari "to frame, construct, build," from fabrica "workshop" (see forge (n.)). Meaning "to counterfeit" (a letter, document, or other writing) is from early 14c.; literal meaning "to form (something) by heating in a forge and hammering" is from late 14c. in English, also used in Middle English of the minting of coins, so that it once meant "issue good money" but came to mean "issue spurious (paper) money." Related: Forged; forging.

forge (v.2)

1769 (with an apparent isolated use from 1610s), "make way, move ahead," of unknown origin, perhaps an alteration of force (v.), but perhaps rather from forge (n.), via notion of steady hammering at something. Originally nautical, in reference to vessels.

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Definitions of forge from WordNet
forge (v.)
create by hammering;
forge a pair of tongues
Synonyms: hammer
forge (v.)
make a copy of with the intent to deceive;
She forged a Green Card
Synonyms: fake / counterfeit
forge (v.)
come up with (an idea, plan, explanation, theory, or principle) after a mental effort;
Synonyms: invent / contrive / devise / excogitate / formulate
forge (v.)
move ahead steadily;
He forged ahead
forge (v.)
move or act with a sudden increase in speed or energy;
Synonyms: spurt / spirt
forge (v.)
make something, usually for a specific function;
Synonyms: shape / form / work / mold / mould
forge (v.)
make out of components (often in an improvising manner);
Synonyms: fashion
forge (n.)
furnace consisting of a special hearth where metal is heated before shaping;
forge (n.)
a workplace where metal is worked by heating and hammering;
Synonyms: smithy