common duckweed: of temperate regions except eastern Asia and Australia
duckweed: any small or minute aquatic plant of the family Lemnaceae that float on or near the surface of shallow ponds
passeriformes: largest order of birds comprising about half the known species; rooks; finches; sparrows; tits; warblers; robins; wrens; swallows; etc.; the four suborders are Eurylaimi and Tyranni and Menurae and Oscines or Passeres