Main Entry: the·oph·yl·line

Pronunciation: \thē-ˈäf-ə-lən\

Function: noun

: a feebly basic bitter crystalline compound C₇H₈N₄O₂ that is present in small amounts in tea but is prepared chiefly by synthesis, that is isomeric with theobromine, and that is used in medicine often in the form of derivatives or in combination with other drugs especially as a bronchodilator to relieve or prevent symptoms of asthma and bronchospasm associated with chronic bronchitis and emphysema