Late 16th century; earliest use found in Henry Lyte (1529–1607), botanist and antiquary. From post-classical Latin ros solis the plant sundew from classical Latin rōs dew + sōlis, genitive of sōl sun, perhaps after Dutch zondauw, †sondauw.
ros solis/rəʊz ˈsɒlɪs/
Are You Learning English? Here Are Our Top English Tips