To encompass means to include or contain everything within a particular scope or boundary. When a history textbook encompasses three centuries, it covers that entire time period. When a nature preserve encompasses 500 acres, all that land falls within its borders.

The word suggests completeness: it means fully including something. A good science curriculum encompasses theory, experiments, and real-world applications. A talented athlete's skills might encompass speed, strength, and strategy.

You can also use encompass when describing physical surroundings. A castle wall encompasses the courtyard and buildings inside it. The Pacific Ocean encompasses thousands of islands.

Think of encompass as drawing a circle around things: whatever falls inside that circle is encompassed. When someone says, “my research encompasses both physics and biology,” they mean their work includes and covers both fields completely.