tinder

Tinder comes from Middle English tinder (also spelled tunder, tender, tonder), from Old English tynder, tracing back to Proto-Germanic *tundrą or *tundrǭ, meaning tinder.

The word has stayed remarkably close to its root meaning across centuries — dry, flammable material ready to catch fire.

It shares its Germanic root with Swedish tända, meaning 'to light' or 'to set on fire,' and with similar words like Dutch tonder and German Zunder, all pointing to the same idea of something ready to burn.