Back the wrong horse

Meaning

Support someone who ends up losing or failing.

Usage

Used for any mistaken commitment.

Origin & History

Origins and dates here are approximate summaries. Many idioms have disputed or unknown origins, and not every date has been checked against a historical dictionary, so treat specific dates and stories as a starting point rather than a citation.

Gambling language from horse racing where a poor bet loses money.

Popular since the nineteenth century as betting metaphors entered everyday English.