Capitulum

noun (plural capitula) Etymology: New Latin, from Latin, small head — more at chapter 1. a rounded protuberance of an anatomical part (as a bone) 2. a racemose inflorescence (as of the sunflower) with the axis shortened and dilated to form a rounded or flattened cluster of sessile flowers — see inflorescence illustration

Энциклопедический словарь Мерриама-Вебстера