Seich may refer to:
- Seich, a commune in the Hautes-Pyrénées department of France
Seiche may refer to:
- Seiche, a standing wave in a body of water
- Seiche (river), a river in Brittany, France, which is a tributary of the Vilaine
- seiche, a French term for a cuttlefish or bobtail squid.
Seiches may refer to:
- Seiches-sur-le-Loir, a commune in the Maine-et-Loire department of France.
Seyches is a commune in the Lot-et-Garonne department of France.
Seitsch is the German name of Siciny, a village in Poland.
Siech may refer to:
- Birte Siech (born 1967), German rower.
Sietch is a locality in the fictional Dune universe created by Frank Herbert.