A bitter crystalline compound present in small quantities in tea leaves, isomeric with theobromine.
- ‘A number of studies have been conducted with the related compound known as theophylline.’
- ‘Three very similar compounds - all in this same group of alkaloids - are present in common beverages, namely caffeine, theophylline, and theobromine.’
- ‘Two related xanthines, theobromine and theophylline, are often present in smaller amounts.’
- ‘It contains not only caffeine but also theophylline, a compound that can ease the symptoms of a cold.’
- ‘While caffeine primarily is active in the brain and muscles, theophylline is active in stimulating the respiratory system, heart and kidneys.’
Late 19th century: from modern Latin Thea (former genus name of the tea plant, from Dutch thee) + Greek phullon leaf + -ine.