palaceous

adjective2

1. •
   (old-fashioned, rare) Resembling a palace.

   • What Domes palaceous! What Cathedrals grand! — 1793
2. •
   (old-fashioned) Of a leaf: having a spade-like shape.

   • Alpina, however, has a black or brownish rachis with scattered palaceous hairs, while that of glabella is entirely smooth and green. — 1901