goldminegold‧mine, gold mine /ˈɡəʊldmaɪn $ ˈɡoʊld-/ noun [countable] 
Examples
The nightclub turned out to be a goldmine.2a place where gold is dug out from a hole in the ground3be sitting on a goldmine to own something very valuable, especially without realizing it
ExamplesEXAMPLES FROM OTHER DICTIONARIES
Thesaurus- His printing business has turned out to be a real goldmine.
- I bet that corner shop's a goldmine.
- It's just a scruffy little beach café, but in summer it's an absolute goldmine.
- Consumerism, the modern goldmine and pipeline, roll merrily along.
- It was loth to do this because the bonds were a potential goldmine when the junk-bond market recovered.
- It was the kiss that did for me, I think, not being called a goldmine.
- Manufacturers of computer-aided design systems are jockeying aggressively to take advantage of this potential goldmine.
- One unfortunate woman who ran a discount shoe store was oblivious to the fact she was sitting on an old school goldmine.
- This was never well stocked and could hardly have been a goldmine.
- Yet, in terms of potential, Sam had a shrewdness and a mind which was akin to an untapped goldmine.
Longman Language Activatorwhen a business produces a profit► profitable
1informal a business or activity that produces large profits: a profitable business or activity makes a profit: · We don't sell children's clothes any more - it wasn't profitable enough.· It's only in the last year that our business has become profitable. Before that we were just managing to cover our costs.
► lucrative a type of business or activity that is lucrative produces a very large profit: · Catering is a very lucrative business if you succeed in it.· Sam's journalistic work was much more lucrative than his painting had ever been.· There is still an illegal but lucrative trade in ivory between Africa and South-East Asia.
► money-spinner British informal a business or product that produces a large profit: · The little bar turned out to be a real moneyspinner.· The toy companies are always trying to find another money-spinner like Monopoly or the Barbie doll.
► goldmine informal a small business, especially a shop or restaurant, that produces a very large profit: · It's just a scruffy little beach café, but in summer it's an absolute goldmine.· I bet that corner shop's a goldmine.
WORD SETS► Industryaggregate, nounalloy, nounamber, nounanneal, verbarc welding, nounasbestos, nounassay, verbautomaker, nounaviation, nounBakelite, nounbasketry, nounbenzene, nounbevel, nounbiodegradable, adjectiveblast, verbblast furnace, nounboom, nounboom town, nounbore, verbbore, nounborehole, nounby-product, nouncane, nouncast, verbcasting, nouncedar, nounchipboard, nounchippings, nouncoalface, nouncollier, nouncolliery, nounconcentrate, nouncondenser, nounconstruction, nounconstructor, nounconverter, nouncork, nouncottage industry, nouncross-grained, adjectivecrude, adjectivedeskill, verbdetonate, verbdetonator, noundetoxification, noundevelopment, noundie, noundie casting, noundiesel, noundiesel fuel, noundiggings, noundrill, verbdrive, verbelectronics, nounend product, nounepoxy resin, nounextrude, verbfabricate, verbfabrication, nounforge, nounfound, verbfoundry, nounglass fibre, noungoldmine, nounground glass, nounhigh technology, nounindustrial, adjectiveindustrial archaeology, nounindustrialism, nounindustrialist, nounindustrialization, nouningot, nouninstallation, nounjute, nounlaminate, nounlaminated, adjectivelaser, nounlatex, nounlight industry, nounlime, nounlode, nounlow-tech, adjectivelubricant, nounlubricate, verbmacadam, nounmacerate, verbmachine, verbmachine tool, nounmachinist, nounmaker, nounmanganese, nounmanufacture, verbmanufacture, nounmasonry, nounmaterial, nounmatrix, nounmeat-packing, nounmetal, nounmetal fatigue, nounmetallic, adjectivemetallurgy, nounmetalwork, nounmill, verbmine, nounmine, verbminer, nounmining, nounmodular, adjectivemodule, nounmolten, adjectivemolybdenum, nounmortise, nounmother lode, nounmould, verbmoulding, nounochre, nounoff-cut, nounoil, nounoil paint, nounopencast, adjectiveoxyacetylene, nounpackaging, nounpaint stripper, nounpaintwork, nounpaling, nounpallet, nounpan, nounpanelling, nounpanel pin, nounpaper, adjectivepapier mâché, nounpatent leather, nounperfumery, nounpit, nounpitch, nounpithead, nounplane, verbplant, nounplywood, nounpost-industrial, adjectiveprocess, nounproduce, verbproduct, nounproduction, nounproductivity, nounpulp, verbpump, verbPVC, nounquarry, nounquartz, nounready-made, adjectiverefine, verbrefined, adjectivereprocess, verbroller, nounrough-hewn, adjectiverubber, nounsafety lamp, nounsandblast, verbsealskin, nounshaft, nounshavings, nounsheeting, nounsheet metal, nounshipbuilder, nounskilled, adjectiveslag, nounslag heap, nounsludge, nounslurry, nounsmelt, verbsmith, nounsmithy, nounsmokestack, nounsmokestack industry, nounsoftwood, nounsolder, nounsolder, verbsoldering iron, nounspirit level, nounspray paint, nounsteam, nounsteel, nounstrip mine, nounStyrofoam, nounsunrise industry, nounsynthesis, nounsynthesize, verbtannery, nountemper, verbtensile strength, nountextile, nounthree-ply, adjectiveunrefined, adjectiveunvarnished, adjectiveupright, nounvarnish, nounvat, nounvinyl, nounvulcanize, verbwarehouse, nounwattle, nounwax, nounwaxen, adjectivewaxy, adjectiveweld, verbweld, nounwelder, nounwickerwork, nounwire, nounwood, nounwood pulp, nounwork, verbworking, nounworkshop, nounwrought iron, nounyarn, noun
The nightclub turned out to be a goldmine.2a place where gold is dug out from a hole in the ground3be sitting on a goldmine to own something very valuable, especially without realizing it