1. Grave in quality or manner.
1. Carried out in earnest: engaged in serious drinking.
2. Deeply interested or involved.
3. Designed for and addressing grave and earnest tastes: serious art.
4. Not trifling or jesting.
5. Of considerable size or scope; substantial.
6. Of such character or quality as to appeal to the expert, the connoisseur, or the sophisticate.
3. Concerned with important rather than trivial matters.
1. Being of such import as to cause anxiety.
2. Too complex to be easily answered or solved.