The Collaborative International Dictionary
Cretan rockrose
Rockrose \Rock"rose`\, n. (Bot.) A name given to any species of the genus Helianthemum, low shrubs or herbs with yellow flowers, especially the European Helianthemum vulgare and the American frostweed, Helianthemum Canadense.
Cretan rockrose, a related shrub ( Cistus Creticus), one of the plants yielding the fragrant gum called ladanum.
Wiktionary
cretan rockrose
n. A shrub, ''Cistus creticus'', related to the rockrose. It yields labdanum.