Akademik

serious
adjective /ˈsɪəriəs/
a) Without humor or expression of happiness; grave in manner or disposition; earnest; thoughtful; solemn.

It was a surprise to see the captain, who had always seemed so serious, laugh so heartily.

b) Important; weighty; not trifling; leaving no room for play; needing great attention; critical.

This is a serious problem. Well need our best experts.

Ant: trifling, unimportant, jesting

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