ceremonial and ceremonious both imply strict attention to what is prescribed by custom or by ritual, but ceremonial applies to things that are associated with ceremonies
a ceremonial offering
, ceremonious to persons given to ceremony or to acts attended by ceremony.
made his ceremonious entrance
formal applies both to things prescribed by and to persons obedient to custom and may suggest stiff, restrained, or old-fashioned behavior.
a formal report
the headmaster's formal manner
conventional implies accord with general custom and usage
conventional courtesy
and may suggest a stodgy lack of originality or independence.
conventional fiction
Example Sentences
Noun he asked her to the formal at the end of the year