River

bayou, Dalles, Ea, eau, Estuary, Flood, Flower, Fluvial, Potamic, Potamology, R, Riverain, Runner, Stream, Tide, Tributary, Waterway

Rivers:

2 letters: Ay, Hué, Ob, Po, Si, Xi

3 letters: Aar, Aln, Axe, Ayr, Bug, Cam, Dee, Don, Ems, Esk, Exe, Fal, Fly, Fox, Han, Hsi, Inn, Lee, Lot, Luo, Lys, Mur, Nar, Oil, Oka, Ord, Red, Tay, Tet, Ure, Usk, Wye, Yeo

4 letters: Abus, Abzu, Acis, adda, Adur, Aire, Alma, Alph, Amur, Aran, Aras, Arno, Aude, Avon, Back, Beni, Bomu, Cher, Culbá, Culm, Dart, Deva, Doon, Dove, Drin, Earn, East, Ebbw, Ebro, Eden, Eder, Elbe, Erne, Esla, Eure, Gila, Gota, Huon, Idle, Isar, Iser, Isis, isla, Jiul, Juba, Juruá, Kama, Kill, Kura, Kwai, Lahn, Lech, Lena, Liao, Luan, Lune, Maas, Main, Meta, Milk, Mole, Nene, Neva, Nile, Nith, Oder, Ohio, Oise, Ouse, Oxus, Prut, Rhône, Rock, Ruhr, Saar, Saône, Sava, Soar, Spey, Styx, Swan, Swat, Taff, Tana, Tarn, Tees, Teme, Test, Tone, Tyne, Uele, Ural, Uvod, Vaal, Waal, Wear, Xero, Yalu, Yare, Yate, Yser, Yuan, Yuen

5 letters: Abana, Acton, Adige, Afton, Agate, Aisne, Aldan, Apure, Argun, Avoca, Benue, Boyne, Broad, Cauca, Chari, Clyde, Clyst, clwyd, Colne, Congo, Conwy, Cross, Dasht, Desna, Doubs, Douro, Drava, Drave, Duero, Dvina, Eblis, Firth, Fleet, Forth, Gogra, Green, Havel, Hotan, Indre, Indus, Isere, Ishim, James, Jumna, Kasai, Kaven, Kenga, Kuban, Lethe, Liard, Limay, Loire, Mamoré, Marne, Mbomu, Meuse, Min(h)o, Mulla, Mures, Namoi, Negro, Neman, Niger, Ogowe, Onega, Oreti, Peace, Pearl, Pecos, Pelly, Piave, Pison, Plate, Purus, Rainy, Rance, Rhine, Rogue, Seine, Shari, Shire, Siang, Siret, Skien, Slave, Snake, Snowy, Somme, Spree, Staff, Stour, Swale, Tagus, Tamar, Tapti, Tarim, Teign, Terek, Tiber, Tisza, Tobol, Trent, Tweed, Volga, Volta, Warta, Weser, Xiang, Xingu, Yaqui, Yarra, Yonne, Yssel, Yukon

6 letters: Allier, Amazon, Anadyr, Angara, Arzina, Atbara, Barcoo, Barrow, Bio-Bio, Broads, Calder, Canton, Chenab, Clutha, Colima, Croton, Crouch, Cydnus, Danube, Dawson, Donets, Duddon, Durack, Escaut, Finlay, Fraser, Gambia, Ganges, Glomma, Granta, Harlem, Hodder, Hsiang, Hudson, Humber, Iguacu, Ijssel, Irtish, Irtysh, Irwell, Isonzo, Itchen, Japura, Javari, Javary, Jhelum, Jordan, Kaduna, Kagera, Kennet, Kistna, Kolyma, Komati, Liffey, Medway, Mekong, Mersey, mindel, Mohawk, Molopo, Morava, Moskva, Murray, Neckar, Neisse, Nelson, Neuquén, Nyeman, Ogooue, Orange, Orwell, Ottawa, Pahang, Parana, Peneus, Platte, Pripet, Prosna, Rakaia, Ribble, Riffle, Rother, Sabine, St John, Salado, Sambre, San(tee), Seneca, Severn, Struma, Sutlej, Swanee, Tanana, Tarsus, Tevere, Teviot, Thames, Ticino, Tigris, Tugela, Tyburn, Ubangi, Ussuri, Vardar, Vienne, Vitava, Vyatka, Wabash, Wairau, Wensum, Wharfe, Wupper, Yarrow, Yellow

7 letters: Acheron, Aruwimi, Bassein, Berbice, Berezua, Bermejo, Buffalo, Burnett, Caqueta, Cauvery, Chagres, Cocytus, Damodar, Darling, Derwent, Detroit, Dnieper, Dubglas, Durance, Ettrick, Fitzroy, Garonne, Genesee, Gironde, Guapore, Hari Rud, Helmand, Hooghly, Huang He, Hwangho, Iguassu, Irawadi, Kanawha, Krishna, Lachlan, Limpopo, Lualaba, Madeira, Manning, Maranon, Maritsa, Mataura, Mosel(le), Narbada, Narmada, Niagara, Nipigon, oceanus, Orinoco, Orontes, Parrett, Pechora, Pharpar, Potomac, Red Deer, Rubicon, Sabrina, St Clair, St Croix, St Mary's, Salinas, Salween, Salzach, Sanders, Scheldt, Senegal, Shannon, Songhua, Tapajos, Thomson, Tugaloo, Ucayali, Uruguay, Vistula, Waikato, Washita, Wateree, Welland, Yangtse, Yenisei, Yenisey, Zambese, Zambezi

8 letters: Amu Darya, Anderson, Apurimac, Araguaia, Araguaya, Arkansas, Berezina, Blue Nile, Canadian, Charente, Cherwell, Chindwin, Chu Kiang, Clarence, Colorado, Columbia, Congaree, Daintree, Demerara, Dneister, Dordogne, Flinders, Franklin, Gascoyne, Godavari, Granicus, Guadiana, Hamilton, Illinois, Kentucky, Klondike, Kootenay, M(a)eander, Mahanadi, Manawatu, Menderes, Missouri, Mitchell, Ocmulgee, Okanagan, Okavango, Okovango, Ouachita, Pactolus, Paraguay, Parnaiba, Putumayo, Rio Negro, Safid Rud, Saguenay, Savannah, S(u)wannee, Syr Darya, Tonle Sap, Torridge, Toulouse, Tunguska, Van Hades, Veronezh, Victoria, Volturno, Wanganui, Windrush, Zhu Jiang

9 letters: Allegheny, Ashburton, Billabong, Churchill, Crocodile, Des Moines, Essequibo, Euphrates, Irrawaddy, Kuskokwim, Mackenzie, Magdalena, Murchison, Parnahiba, Perihonca, Pilcomayo, Porcupine, Qu'Appelle, Rangitata, Richelieu, Rio Branco, Rio Grande, St George's, Salambria, Santa Cruz, White Nile, Wisconsin

10 letters: Black Volta, Blackwater, Chao Phraya, Courantyne, Cumberland, Great Slave, Housatonic, Kizil Irmak, Phlegethon, Rangitaiki, Rangitikei, Sacramento, St Lawrence, San Joaquin, Schuylkill, White Volta, Yesil Irmak

11 letters: Aegospotami, Assiniboine, Brahmaputra, Connecticut, Cooper Creek, Delaguadero, Guadalentin, Lesser Slave, Madre de Dios, Mississauga, Mississippi, Monongahela, Saõ Francisco, Shatt-al-Arab, Susquehanna, Yellowstone

12 letters: Guadalquivir, Murrumbidgee, Saskatchewan

13 letters: Little Bighorn

17 letters: North Saskatchewan, South Saskatchewan

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