Late 17th century. From French majestueux, either from post-classical Latin maiestuosus majestic, or independently in French from majesté + -ueux, after e.g. somptueux, voluptueux.
Definition of majestuous in US English:
majestuous
adjective
rare
Majestic.
Origin
Late 17th century. From French majestueux, either from post-classical Latin maiestuosus majestic, or independently in French from majesté + -ueux, after e.g. somptueux, voluptueux.