# supplementary

/ˌsəpɫəˈmɛnɝi/ (US) · /sˌʌplɪmˈɛntəɹi/ (UK)

Source: https://englishreference.com/word/supplementary
Updated: 2026-08-08

## Senses

### 1. extra or additional

adjective · CEFR B2 · Academic

added to something else to provide more information or to help complete it.

For teachers: functioning as an addition to something else in order to complete it or provide further detail.

- The teacher gave us supplementary reading to help us understand the history lesson.
- The report includes supplementary data in the appendices to support the primary findings presented in the executive summary.

Usage: Often used before a noun to describe materials, information, or income.

Teaching tip: This is a common word in academic and formal contexts; students should use it instead of 'extra' when writing essays or business reports.

### 2. an extra item

noun · CEFR C1 · Formal

an extra part or thing that is added to something else.

For teachers: an item or amount provided as an addition to a standard or primary set.

- The payment includes a small supplementary for the extra work performed.
- The budget allocated a significant supplementary for unforeseen maintenance costs during the winter quarter.

Usage: Less common than the adjective form; often refers to payments or specific document sections.

## Examples

- The teacher gave us supplementary exercises to practice at home.
- The report includes supplementary data in the final pages to support the main findings.
- While the primary text covers the historical events, the supplementary readings provide essential cultural context for understanding the motivations of the key figures involved.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.