tinder

At its heart, "tinder" means dry material that catches a spark easily and helps start a fire. It can be dried grass, thin bark, wood shavings, char cloth, or other light material that burns quickly. Before modern matches and lighters were common, people depended on tinder to turn a small spark into a steady flame.

You may also see the word in the name of the dating app Tinder, which plays on the idea of a spark leading to something more. But in normal English, the main meaning of "tinder" is still the material used to get a fire going.

The word "tinder" comes from the old, practical world of making fire by hand. For centuries, tinder was the small, dry, easy-to-burn material people used to catch a spark before feeding a larger fire. Dried plant fibers, shredded bark, paper, wood shavings, and char cloth could all serve this purpose. Good tinder did not burn for long, but it burned fast enough to help light kindling and then larger pieces of wood.

Because of that basic meaning, the word is also used in a broader descriptive way. If grass, wood, or a forest is described as "dry as tinder," it means it is so dry that it could catch fire very easily. This is why the word often appears in writing about wildfires, heat, and dangerous dry conditions.

You may also recognize Tinder as the name of a dating app. That use comes from the same image of a spark starting something. Still, the core meaning of the common noun "tinder" is the fire-starting material itself. Related expressions such as "tinderbox" build on that same idea and describe a situation that could flare up suddenly.