Definition of "theobromine" [the•o•bro•mine]

• A bitter, colorless alkaloid, C7H8N4O2, derived from the cacao bean, found in chocolate products and used in medicine as a diuretic, vasodilator, and myocardial stimulant. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "The biggie that most people have heard about is the caffeine relative called theobromine, which is the one usually shown on "I heart chocolate" tee-shirts, so that's a good place to start, with its trippy endorphins to create a pleasant buzz."
• "* Chocolate in any form is extremely toxic to man's best friend as it contains a harmful chemical called theobromine, which is fine for humans but is very dangerous for dogs"
• "Chocolate is the richest known source of a little-known substance called theobromine, a close chemical relative of caffeine."