tunicate adjective 3noun 1forms 1 adjective3 •Enclosed in a tunic or mantle; covered or coated with layers.This tunicate withered hag the Señora had my financial number. — 1976 •Of or pertaining to Tunicata or Urochordata. •Having each joint buried in the preceding funnel-shaped one, as in certain antennae of insects. noun1 •Any of very many chordate marine animals, of the subphyla Tunicata or Urochordata, including the sea squirts. formstunicates