altiloquent
/alˈtɪləkw(ə)nt/Now rare
adjective
Of speech, writing, etc.: characterized by altiloquence; loud, elevated, pompous, or high-flown. Occasionally also of a person: using such language.
Origin
Mid 17th century; earliest use found in Thomas Blount (1618–1679), antiquary and lexicographer. From alti- + -loquent, after altiloquence.