• (n.) An herb (Epilobium spicatum) with showy purple flowers, common in Europe and North America; -- called also great willow herb. • (n.) the oleander. • (n.) Any shrub of the genus Rhododendron. Found on http://thinkexist.com/dictionary/meaning/rosebay/
Rose'bay` noun (Botany) (a) the oleander. [ Obsolete] (b) Any shrub of the genus Rhododendron . [ U.S.] (c) An herb ( Epilobium spicatum ) with showy purple flowers, common in Europe and North America; -- called also great willow herb . Found on http://www.encyclo.co.uk/webster/R/94