phosphorescents, phosphorescence

The words phosphorescents, phosphorescence sound the same but have different meanings and spellings. Why do phosphorescents, phosphorescence sound the same even though they are completely different words?

The answer is simple: phosphorescents, phosphorescence are homophones of the English language.

phosphorescence
  1. :: noun

    Persistent emission of light following exposure to and removal of incident radiation.

  2. :: noun

    Emission of light without burning or by very slow burning without appreciable heat, as from the slow oxidation of phosphorous: "He saw the phosphorescence of the Gulf weed in the water” ( Ernest Hemingway).

phosphorescents
  1. :: noun

    Plural form of phosphorescent.

Definitions from The American Heritage® Dictionary of the English Language, 4th Edition, from Wiktionary, Creative Commons Attribution/Share-Alike License and Wordnik.

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About Homophones

Homophones (literally "same sound") are usually defined as words that share the same pronunciation, regardless of how they are spelled.

If they are spelled the same then they are also homographs (and homonyms); if they are spelled differently then they are also heterographs (literally "different writing").