Definitions
01not joking or funny
A2 · Elementary
adj. quiet and thinking carefully, without laughing or making jokes.
adj. characterized by a grave or somber disposition; lacking humor or levity in manner.
日本語:真面目※
“The teacher looked very serious when he told the students to be quiet.”
“The lead investigator maintained a serious expression throughout the briefing, refusing to indulge in the lighthearted banter of his colleagues.”
02important or dangerous
A2 · Elementary
adj. important and needing a lot of thought because it could cause problems.
adj. having significant or dangerous consequences; not trivial or slight.
日本語:深刻※
“The doctor said it was a serious injury and she needed to stay in the hospital.”
“The board of directors met to discuss the serious financial implications of the failed merger, acknowledging that the company's future was at stake.”
Antonyms
03sincere and honest
B1 · Intermediate
adj. really meaning what you say and not just pretending or playing.
adj. acting in earnest; sincerely intending to carry out a stated plan or promise.
日本語:真剣※
“Are you serious about moving to another country for work?”
“Despite his reputation for sarcasm, he was entirely serious when he offered to fund the local community project.”
Antonyms
04very committed
B1 · Intermediate
adj. giving a lot of time and energy to an activity because you care about it.
adj. deeply interested in or devoted to a particular activity or subject.
“She is a serious student who spends every weekend in the library.”
“As a serious collector of rare manuscripts, he spent decades scouring European auctions to complete his primary research library.”
Antonyms
05seriously
C1 · Advanced Informal · Dialect
adv. used in some phrases to mean 'in a serious way'.
adv. functioning as an adverbial modifier, particularly in fixed collocations like 'take serious' or 'mean serious'.
“You shouldn't take him too serious when he is in a bad mood.”
“The foreman warned the crew that the safety inspector would take any violations serious, regardless of past performance.”
Usage
In standard English, 'seriously' is required; this form is restricted to specific informal or regional speech patterns.
Collocations
Common phrases and expressions where native English speakers use the word “serious” in context.
Real-World Examples
“Articles on AI safety warnings have described the technology as posing a serious threat to our existence.” “Democrats and Republicans on the Homeland Security Committee had “serious questions” for OpenAI, more than 30 members of Congress called for federal guardrails, and 15 Attorneys General warned Altman to preserve records of the incident.” Etymology
From Middle English seryows, from Old French serieux, from Medieval Latin sēriōsus, an extension of Latin sērius (“grave, earnest, serious”), from Proto-Indo-European *swer- (“heavy”). Cognate with German schwer (“heavy, difficult, severe”), Old English swǣr (“heavy, grave, grievous”). More at swear, sweer.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.
Word family
NOUN
ADJECTIVE
ADVERB
- Exam level
- CambridgeCambridgeCambridge English QualificationsThe exam suite from Cambridge University Press & Assessment, from A1 Movers up to C2 Proficiency. The benchmark names double as CEFR labels.A2 KeyIELTSIELTSInternational English Language Testing SystemThe 0–9 band test co-owned by the British Council, IDP, and Cambridge. Used for university entry, work, and migration.3.0–4.0TOEFL iBTTOEFL iBTTest of English as a Foreign Language, Internet-Based TestETS's academic English test, the standard route for US university admissions. Scored 0–120, with a 1–6 scale since 2026.1–6 scale: 2.0–2.524–43TOEICTOEICTest of English for International CommunicationETS's workplace English test, big in Japan and Korea. Listening & Reading scores 10–990 and tops out at C1.225–549
- Frequency
- Very common
- Level
- A2 · ElementaryOxford
- Updated
- アルファベット
- 読み方の一覧 →
QR code
englishreference.com/q/serious
※ 機械で選んだ訳語です。ネイティブスピーカーによる確認はまだです。
「日本語」「カタカナ語」 data: JMdict (EDRDG), CC BY-SA 4.0