[ fō′tō-kăt′l-ĭst ]
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A substance that helps bring about a light-catalyzed reaction, such as chlorophyll in photosynthesis.
GOOSES. GEESES. I WANT THIS QUIZ ON PLURAL NOUNS!
Test how much you really know about regular and irregular plural nouns with this quiz.
Question 1 of 9
Which of the following nouns has an irregular plural form?
Words nearby photocatalyst
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.