• Webster's Revised Unabridged Dictionary
    • n Lutidine (Chem) Any one of several metameric alkaloids, C5H3N.(CH3)2, of the pyridine series, obtained from bone oil as liquids, and having peculiar pungent odors. These alkaloids are also called respectively dimethyl pyridine ethyl pyridine, etc.
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Century Dictionary and Cyclopedia
    • n lutidine The collective name of the various isomeric dimethylpyridines, (CH3)2C5H3N. They are present in coal-tar oil and in animal-and bone-oil, and resemble pyridine in general properties.
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Webster's Revised Unabridged Dictionary
From toluidine, by transposition


In literature:

When distilled with potassium hydrate it yields quinoline, lutidine, and two isomeric collidines.
"Scientific American Supplement, No. 415, December 15, 1883" by Various