English Reference

Word

sideline

Phoneticsside·line, stress on the first syllable

US/ˈsaɪdˌɫaɪn/

UK/sˈaɪdlaɪn/

Countable noun

Definition

n. the line that marks the side of a sports field. It also refers to a job or activity you do in addition to your main work.

n. the boundary line extending along the side of a playing field; by extension, a secondary occupation or interest pursued alongside a primary career.

Examples

“The coach stood on the sideline shouting instructions.”

“She works as a lawyer but has a profitable sideline selling handmade jewelry online.”

“While the athlete was forced to watch from the sideline due to injury, he began developing a business sideline in sports commentary that eventually became his full-time profession.”

Examples

simple

“The coach stood on the sideline shouting instructions.”

contextual

“She works as a lawyer but has a profitable sideline selling handmade jewelry online.”

complex

“While the athlete was forced to watch from the sideline due to injury, he began developing a business sideline in sports commentary that eventually became his full-time profession.”

Usage

Often used in the plural ('the sidelines') when referring to the area just outside the field of play.

Real-World Examples

“Fellow new signing Bruno Guimaraes was hardly missed after being sidelined by an injury suffered in last weekend’s Community Shield win over Manchester City.”
Al Jazeera 21 Aug 2026
“Baleba, who joined Brighton from Lille in 2023, is currently sidelined with an ankle injury he picked up during their pre-season training camp in Austria.”
BBC News 21 Aug 2026
“The Argentina goalkeeper is currently sidelined due to a finger injury.”
The Guardian 17 Aug 2026

Etymology

From side + line.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

Domain

Sports

This entry

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.B2 FirstIELTSIELTSInternational English Language Testing SystemThe 0–9 band test co-owned by the British Council, IDP, and Cambridge. Used for university entry, work, and migration.5.5–6.5TOEFL 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: 4.0–4.572–94TOEICTOEICTest of English for International CommunicationETS's workplace English test, big in Japan and Korea. Listening & Reading scores 10–990 and tops out at C1.785–944
Frequency
Frequent
Level
B2 · Upper Intermediate
Updated

QR code

englishreference.com/q/sideline

English Reference