Ansa or ANSA can refer to any of the following:
- Ansa, Queen of the Lombards, 8th century, wife of Desiderius, king of the Lombards
- Ansa (moth), genus of moth
- Ansa (Hinduism) or Aṃśa in Hinduism, a solar deity and one of the Adityas.
- ansa as part of Arabic words means "constant"
As the acronym ANSA:
- Artists for a New South Africa, nonprofit organization working in the U.S. and South Africa to combat HIV/AIDS, assist children orphaned by the disease, advance human and civil rights
- Agence nouvelle des solidarités actives, association créée en janvier 2006 par Martin Hirsch
- Afghan National Standards Association, the ISO representative organization for Afghanistan.
- Agenzia Nazionale Stampa Associata, Italian news agency
- Ansa Mediterranean or ANSAmed, section of the above
- Association of Norwegian Students Abroad
- Applied Neuroscience Society of Australasia
- Australian Network of Student Anthropologists, student-run arm of the Australian Anthropological Society.
- ANSA, an Italian manufacturer of OEM exhaust systems for automobiles.
- ANSA Pre-processor, commercial pre-processing software (Automatic Net-generation for Structural Analysis).
- The Planet of the Apes equivalent of NASA; it is never made clear in the movies what the letters actually stand for.
- ANSA Business, watch retailer based in The Netherlands
ansa is Latin for "handle". It has several uses derived from this meaning:
- In anatomy, the word is applied to nervous structures which resemble loops (for example the ansa lenticularis, ansa cervicalis, Loop of Henle (ansa nephroni) or the ansa of the tympanal organ).
- In archaeology it is used for the engraved and ornamented handle of a vase, which has often survived when the vase itself, being less durable, has disappeared.
- In astronomy, one of the apparent ends of the rings of Saturn as seen in perspective from the earth: so-called because, in the earlier telescopes, they looked like handles projecting from the planet.
- In chemistry, it is used to describe a bridge between two functional groups/ligands.
- In the plural ansae, in astronomy, compact nebulosities such as can be found in protoplanetary nebulae.