Foreseeable means able to be predicted or expected based on what you already know. If something is foreseeable, you can reasonably imagine it happening before it actually does.

When meteorologists forecast rain for tomorrow, getting wet while walking to school is foreseeable: you know it's coming, so you can prepare by bringing an umbrella. When you don't study for a spelling test, a poor grade becomes foreseeable. The outcome isn't certain, but it's predictable enough that you shouldn't be surprised.

The word often appears in the phrase in the foreseeable future, meaning during a time period you can reasonably predict. If your family has no vacation plans in the foreseeable future, you're not expecting to travel anytime soon, though something could change. If a friend says she'll be busy with soccer for the foreseeable future, she means for as long as she can currently predict, probably through the end of the season.

Something unforeseeable is the opposite: completely unexpected, like a surprise party or a sudden snowstorm in May. Good planning often means thinking about foreseeable problems and preparing for them, such as bringing extra batteries on a camping trip, starting a big project early, or saving money for foreseeable costs.