Dive (verb)

1. To plunge headfirst into water.
2. To descend quickly and steeply.

Origin:

From middle english diven, from old english dīfan ("to dip, immerse"), from proto-germanic *daupijaną ("to dip"), from proto-indo-european *dheub- ("to dive, sink").

Examples:

1. He dove into the pool.
2. She dove into the ocean to swim with the dolphins.
3. He dove off the diving board.
4. The plane dove towards the ground.
5. The stock market dove after the announcement of the new tariffs.