iaa

(noun) a plant hormone promoting elongation of stems and roots. Synonyms: indoleacetic acid, IAA.

(noun) Yemen-based terrorist group that supports al-Qaeda's goals; seeks to overthrow the Yemeni government and eliminate United States interests; responsible for bombings and kidnappings and killing western tourists in Yemen. Synonyms: Islamic Army of Aden, IAA, Islamic Army of Aden-Abyan, Aden-Abyan Islamic Army.