adjective

1. 1. observed or done according to ritual or tradition: said esp. of religious holidays, rites, etc.
   2. sacred in character
2. according to strict form; formal a solemn ceremony
3. 1. serious or grave a solemn face
   2. deeply earnest; very sincere a solemn oath
4. very impressive or arousing feelings of awe because of its great importance or seriousness a solemn occasion
5. somber because dark in color

Etymology: ME solemne < OFr < L sollemnis, sollennis, yearly, annual, hence religious, solemn (from assoc. with annual religious festivals) < sollus, all, entire < Oscan, akin to L salvus (see safe) + ? annus, year