Origin: Latin suffix -ous
Serious has 8 different meanings across 1 category:
concerned with work or important matters rather than play or trivialities
"a serious student of history"
"a serious attempt to learn to ski"
"gave me a serious look"
"a serious young man"
"are you serious or joking?"
"Don't be so serious!"
requiring effort or concentration; complex and not easy to answer or solve
"raised serious objections to the proposal"
"the plan has a serious flaw"
Without humor or expression of happiness; grave in manner or disposition
"After hearing the bad news, he sat silently with a serious face, offering no smile to comfort his friend."
In plain English: Serious means being very important, not joking around, or dealing with something that has real consequences.
"She took the news very seriously and decided to make some changes in her life."
Usage: Use serious to describe someone with a solemn, unamused demeanor rather than one who is simply busy or important. Distinguish it from severe when referring specifically to the absence of laughter and light-heartedness.
In a serious manner; seriously.
"She asked him to stop joking and speak about the accident in a serious manner before calling an ambulance."
In plain English: Seriously means doing something with real effort and not just joking around.
"She looked at me seriously when I told her about my plans."
The word "serious" comes from the Latin root meaning "grave," which ultimately traces back to a Proto-Indo-European term for "heavy." This connection explains why related words in German and Old English also carry meanings of weight or severity.