# syphilis

/ˈsɪfəɫɪs/ (US) · /sˈɪfəlɪs/ (UK) · CEFR C1 · Noun

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

## Definition

a serious disease that people get by having sex with someone who is already infected. It is caused by bacteria and can damage the body if a doctor does not treat it with medicine.

For teachers: a chronic bacterial infection, caused by the spirochete Treponema pallidum, primarily transmitted through sexual contact. If left untreated, it progresses through distinct clinical stages and can cause systemic damage to the heart, brain, and nervous system.

## Examples

- Doctors use antibiotics to treat syphilis effectively.
- Public health clinics offer free testing for syphilis to help prevent the spread of the infection within the community.
- Historically, syphilis was a major cause of neurological decline before the advent of penicillin, which remains the primary treatment for eradicating the bacteria in its early stages.

## Usage notes

- Uncountable in its medical sense; typically takes a singular verb.

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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.