Unreachable means impossible to get to, contact, or achieve. When someone is unreachable, you can't get in touch with them no matter how you try: their phone goes straight to voicemail, they don't respond to messages, and they seem to have vanished. A mountain cabin might be unreachable during winter when snow blocks all the roads leading to it.

The word also describes goals or objects that seem impossible to obtain. A basketball hoop might feel unreachable when you're too short to dunk, or a shelf might be unreachable without a stepstool. Students sometimes worry that their dreams are unreachable.

In technology, unreachable describes a computer or server that can't be connected to, perhaps because of network problems. A website becomes unreachable when the server is down or your internet connection fails.

The opposite feeling of something being unreachable is when it's within reach: close enough to touch, contact, or achieve. What seems unreachable today might become perfectly reachable tomorrow with growth, new tools, or a different approach.