Plants

• Sedge, any of the numerous plants in the sedge family, Cyperaceae
• Sedge or sweet sedge, a name for sweet flag (Acorus calamus), a marshland plant in the Acoraceae family
• Sedge, a name for yellow flag iris (Iris pseudacorus), a marshland plant in the iris family
• Sedge, a bed of large sedges or similar plants, usually growing in damp ground or shallow water: a type of fen

Animals

Insects

• Sedge or sedge-fly, any of the caddisflies (Trichoptera), small moth-like insects with aquatic larvae
• Sedge darner or common hawker (Aeshna juncea), a dragonfly of Eurasia and North America
• Sedge moth, any of the small moths in the family Glyphipterigidae, whose caterpillars feed on sedges and rushes

Amphibians

• Sedge and bush frogs, the frogs of the mainly African family Hyperoliidae
• Sedge frog, either of two species of Australian tree frog in the large genus Litoria:
• Cooloola Sedge Frog (Litoria cooloolensis)
• Wallum Sedge Frog (Litoria olongburensis)

Reptiles

• Sedge viper (Atheris nitschei), an African snake

Birds

• Sedge, a collective noun for either bitterns or cranes: see List of collective nouns for birds
• Sedge Warbler (Acrocephalus schoenobaenus), a small bird of dense waterside vegetation in Europe, Asia and Africa
• Sedge Wren (Cistothorus platensis), a small wetland species of bird of North and South America

Places

• Little Sedge Island, an island in Barnegat Bay, New Jersey, United States
• Middle Sedge Island, an island in Barnegat Bay, New Jersey, United States
• Sedge Island, an island in the Falklands archipelago
• Sedgemoor, a district in Somerset, England

People

• John Sedges, a pen-name of American author Pearl S. Buck
• Sedge Moore, stage name of the bass player with The Wurzels, a Scrumpy and Western band from Somerset, England

Boats

• , a United States coastguard cutter: see List of United States Coast Guard cutters

Other

• Sedge hat or conical hat, a type of straw hat worn in East Asia
• Sedge, nickname of Liversedge F. C., a football (soccer) club in West Yorkshire, England