Definition of fluorescein
: a yellow or red crystalline dye C20H12O5 with a bright yellow-green fluorescence in alkaline solution
Recent Examples of fluorescein from the Web
Our doctor placed yellow drops containing fluorescein sodium in his eye.
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First Known Use of fluorescein
Medical Definition of fluorescein
: a yellow or red crystalline dye C20H12O5 with a bright yellow-green fluorescence in alkaline solution that is used as the sodium salt as an aid in diagnosis (as of lesions and foreign bodies in the cornea or of brain tumors)
Learn More about fluorescein
Britannica.com: Encyclopedia article about fluorescein
Seen and Heard
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