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August 1, 2026Short & citedBlog
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Field Notes • Crustacean

Crawfish

Crawfish is a common name for several freshwater crustaceans, especially crayfish, and in some regions also for certain marine crustaceans such as spiny lobsters.

Updated August 1, 20261 min readCited sources

Crawfish is a common name for freshwater crustaceans, especially crayfish, and in some regions also for certain marine crustaceans such as spiny lobsters. They are not fish; they are shellfish related to lobsters, crabs, and shrimp.

What it is

Crawfish is a regional name for crayfish, small decapod crustaceans related to lobsters. Some dictionaries also record a saltwater meaning, especially spiny lobster, depending on the region. They are crustaceans, not fish.

Key details

Most crawfish live in freshwater habitats such as rivers, streams, lakes, swamps, and ditches. They feed on both plant and animal matter, including detritus. In the Southern United States, especially Louisiana, they are commonly eaten boiled or steamed.

Regional usage

The word crawfish is used differently by region and can overlap with crayfish or, in some places, spiny lobster. In Canada, crawfish is less common than crayfish in general usage, and some regional dictionaries note unrelated slang or meanings in Quebec.

In short

  • Crawfish is another name for crayfish, and in some regions for spiny lobster.
  • They are crustaceans, not fish, and live mainly in freshwater.
  • Commonly eaten boiled or steamed, especially in the Southern US.
  • Regional vocabulary varies; in Canada, crayfish is more common.
Canadian angle

In Canada, crawfish is less common than crayfish in general usage, and some Canadian regional dictionaries note unrelated slang or regional meanings in Quebec.[6]

Quick questions

What is a crawfish?
A crawfish is a crustacean, usually another name for a crayfish; in some regions it can also refer to a spiny lobster.
Are crawfish and lobster the same?
No. Crawfish are generally smaller freshwater crustaceans, while lobsters are marine crustaceans, though both are related.
Is crawfish a fish?
No. Crawfish are crustaceans, not fish.

Sources

  1. Merriam-Webster — https://www.merriam-webster.com/dictionary/crawfish
    Supports: Defines crawfish as crayfish sense 1 and also notes a spiny lobster sense.
  2. Vocabulary.com — https://www.vocabulary.com/dictionary/crawfish
    Supports: Describes crawfish as a freshwater shellfish/crustacean resembling a small lobster and notes culinary usage.
  3. Cambridge Dictionary — https://dictionary.cambridge.org/us/dictionary/english/crawfish
    Supports: Defines crawfish as a small animal similar to a lobster that lives in rivers and streams and is eaten as food.
  4. Dictionary.com — https://www.dictionary.com/browse/crawfish
    Supports: States crawfish is another name for crayfish and says crawfish are shellfish, not fish.
  5. The Spruce Eats — https://www.thespruceeats.com/what-are-crawfish-4771895
    Supports: Explains crawfish as freshwater crustaceans, notes they are boiled or steamed, and mentions habitat and culinary popularity.
  6. Wiktionary — https://www.wiktionary.org/wiki/crawfish
    Supports: Shows regional senses including freshwater crayfish, marine crustaceans in some regions, and Quebec slang usage.
  7. Oxford Learner's Dictionaries — https://www.oxfordlearnersdictionaries.com/us/definition/english/crayfish
    Supports: Defines crayfish as an animal like a small lobster that lives in rivers and lakes and can be eaten.
  8. Wikipedia — https://en.wikipedia.org/wiki/Crayfish
    Supports: Summarizes crayfish biology, habitat, and diet; useful for general ecological context.