# cancerous

/ˈkænsɝəs/ (US) · /kˈænsəɹəs/ (UK) · CEFR C1 · Adjective

Source: https://englishreference.com/word/cancerous
Updated: 2026-05-08

## Definition

describing cells or growths that are harmful and can spread through the body. It is also used to describe something that is very bad and spreads quickly, like a toxic attitude.

For teachers: relating to or affected by a malignant growth or tumor. In a figurative sense, it describes something harmful or destructive that spreads uncontrollably within a system or group.

## Examples

- The doctor removed a cancerous growth from the patient's arm.
- The lab results confirmed that the tissue was cancerous and required immediate treatment to prevent it from spreading.

## Usage notes

- Often used predicatively after linking verbs like 'is' or 'became', or attributively before a noun.

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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.