adjective
1.
Synonyms: ceremonial , ceremonious, conventional, formal, stately
Related Word: full, plenary; august, grand, impressive, magnificent, majestic, overwhelming; ostentatious
2.
Synonyms: serious 1, earnest, grave, no-nonsense, sedate, sober, sobersided, somber, staid, weighty
Idioms: as solemn as an owl, grave as an undertaker