# What does 'sick as a horse' mean?

'Sick as a horse' means nausea unrelieved by vomiting — Brewer notes a horse cannot vomit, so its nausea is more lasting and more violent than a person's. Brewer's Dictionary of Phrase and Fable (1898), human-proofread transcription on English Wikisource records: “Nausea unrelieved by vomiting. A horse is unable to vomit, because its diaphragm is not a complete partition in the abdomen, perforated only by the gullet, and against which the stomach can be compressed by the abdominal muscles, as is the case in man. Hence the nausea of a horse is more lasting and more violent. (See Notes and Queries , C.S. xii., August 15th. 1885, p. 134.)”

## What it means

- Verbatim from Brewer's (1898): Nausea unrelieved by vomiting. A horse is unable to vomit, because its diaphragm is not a complete partition in the abdomen, perforated only by the gullet, and against which the stomach can be compressed by the abdominal muscles, as is the case in man. Hence the nausea of a horse is more lasting and more violent. (See Notes and Queries , C.S. xii., August 15th. 1885, p. 134.)

## Action steps

1. Modern usage: 'Sick as a horse' means nausea unrelieved by vomiting — Brewer notes a horse cannot vomit, so its nausea is more lasting and more violent than a person's.
2. When quoting the origin, cite Brewer's Dictionary of Phrase and Fable (1898) — this is a 19th-century record, not a modern etymology.

## Sources

- [Brewer's Dictionary of Phrase and Fable (1898) — Wikisource proofread text](https://en.wikisource.org/wiki/Brewer%27s_Dictionary_of_Phrase_and_Fable/Sick_as_a_Horse)

---
Canonical: https://bestidiomanswers.com/answers/sick-as-a-horse
Author: Best Idiom Answers — https://bestidiomanswers.com
Publisher: Best Idiom Answers
Published: 2026-07-18T14:09:18.640416+00:00
Modified: 2026-07-18T14:34:10.39672+00:00
Last verified: 2026-07-18
License: Citation License 1.0 — https://bestexpertanswers.com/license
© Adolicious LLC