long
Extending far in distance or lasting a lot of time.
Long describes something that extends far in distance or continues for a great amount of time. A long hallway stretches out ahead of you, taking many steps to reach the end. A long book might have 500 pages, while a long movie runs past two hours.
The opposite of long is short. A short pencil barely fits in your hand, while a long pencil extends well beyond your grip. When you're waiting for something you want, five minutes can feel incredibly long, but when you're having fun, five hours might seem short.
People use “long” in many expressions. Before long means “soon” (Before long, summer vacation will arrive). In the long run means considering what happens over time, not just immediately (Practicing piano feels tedious now, but in the long run, you'll be glad you stuck with it). When you say you've known someone for a long time, you mean your friendship extends back many months or years.
You can also long for something, which means to want it intensely. A homesick traveler might long for their own bed. Here, longing is a deep desire or yearning.
The word works for physical space (a long road), duration (a long winter), and even objects that extend in one direction (a long wooden plank, long hair).