any of various seaweeds that grow on rocks exposed at low tide
rockweed in American English
(ˈrɑkˌwid)
noun
any of a number of seaweeds, as fucus, that grow on rocks
rockweed in American English
(ˈrɑkˌwid)
noun
a fucoid seaweed growing on rocks exposed at low tide
Word origin
[1620–30; rock1 + weed1]This word is first recorded in the period 1620–30. Other words that entered Englishat around the same time include: acid, contact, geometric, grommet, settlement