From The Collaborative International Dictionary of English v.0.48 :
Catchfly \Catch"fly\, n. (Bot.) A plant with the joints of the stem, and sometimes other parts, covered with a viscid secretion to which small insects adhere. The species of Silene are examples of the catchfly. [1913 Webster]From WordNet (r) 3.0 (2006) :
catchfly n 1: any plant of the genus Silene [syn: silene, campion, catchfly] 2: mostly perennial herbs with sticky stems that catch insects; widespread in north temperate zone [syn: lychnis, catchfly]