Early 17th century; earliest use found in Thomas Dekker (c1572–1632), playwright and pamphleteer. From classical Latin Palātiumpalace + -ous; compare -acious, -ious.
Definition of palacious in US English:
palacious
adjectivepəˈleɪʃəs
rare
Palatial.
Origin
Early 17th century; earliest use found in Thomas Dekker (c1572–1632), playwright and pamphleteer. From classical Latin Palātium palace + -ous; compare -acious, -ious.