Word.ws English Dictionary

Jordan's rule

Jordan's rule proper noun: an ecogeographic rule describing the inverse relationship between water temperature and meristic characteristics in various species of fish, including the fact that fin ray, vertebrae, or scale numbers increase with decreasing temperature.

Proper noun

Jordan's rule

  1. An ecogeographic rule describing the inverse relationship between water temperature and meristic characteristics in various species of fish, including the fact that fin ray, vertebrae, or scale numbers increase with decreasing temperature.
  2. An ecogeographic rule stating that, given any species in any region, the nearest related species is not likely to be found in the same region nor in a remote region, but in a neighbouring district separated from the first by a barrier of some sort.
    Synonyms:
    Jordan's law

Synonyms of Jordan's rule

Origin of Jordan's rule

Named after American scientist David Starr Jordan (1851–1931).

Questions about Jordan's rule

What does Jordan's rule mean?
Jordan's rule means an ecogeographic rule describing the inverse relationship between water temperature and meristic characteristics in various species of fish, including the fact that fin ray, vertebrae, or scale numbers increase with decreasing temperature.
What part of speech is Jordan's rule?
Jordan's rule is a proper noun.

Words near Jordan's rule in the dictionary

  1. Jordan rule
  2. Jordan Springs
  3. Jordan Valley
  4. Jordan's law
  5. Jordan's Principle
  6. Jordan's rule
  7. Jordana
  8. Jordanes
  9. Jordanesque
  10. Jordanhill
  11. Jordanian

Source and license

Adapted from Wiktionary: Jordan's rule (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

Last updated:

Cite this entry: “Jordan's rule.” Word.ws, https://word.ws/jordan%27s_rule. Based on Wiktionary, CC BY-SA 4.0.