Frisian(s) most often refers to:
- Frisia, a cross-border coastal region in Germany and the Netherlands
- Frisians, the medieval and modern ethnic group inhabiting Frisia
- Frisii, the ancient inhabitants of Frisia prior to 600 AD
- Frisian languages, a group of West Germanic languages, including:
- Old Frisian, spoken in Frisia from the 8th to 16th Century
- Middle Frisian, spoken in Frisia from the 16th to 19th Century
- North Frisian language, spoken in Schleswig-Holstein, Germany
- Saterland Frisian language, spoken in Lower Saxony, Germany
- West Frisian language, spoken in Friesland, Netherlands
- Frisian cuisine, the traditional recipes and cooking methods of Frisia
- Frisians, the medieval and modern ethnic group inhabiting Frisia
Frisian or Friesian may also refer to: