To dispatch or send someone; to make someone run or go to a place.
店長は新人を速やかに客先へ走らすよう指示した。
The manager instructed to send the newbie quickly to the client's site.
忙しいから、彼を書類を持って走らしてくれ。
I'm busy, so send him to run the documents over (deliver them).
彼女は町へ買い物を走らされた。
She was sent off to run errands in town.
To make something go fast (a car, horse, boat); to drive or set something in motion.
彼は古い車をレースに出すために無理に走らした。
He pushed the old car to run in the race.
あの馬はよく走らすと速い。
That horse runs fast when driven hard.
夜中、船長は船を暗い海原に向けて走らした。
At night, the captain put the ship on course and had it sail through the dark sea.
To move something quickly (the pen, one's eyes); e.g., to run one's eyes over a text or to scribble quickly.
彼はペンを走らしてノートに要点を書き留めた。
He hurriedly ran his pen across the notebook and jotted down the key points.
資料に目を走らして、重要な箇所に線を引いた。
He ran his eyes over the material and underlined the important parts.
To rout the enemy; to put opponents to flight (a somewhat literary or archaic usage).
将兵たちは敵を打ち破り、敵軍を走らした。
The soldiers defeated the enemy and put their forces to flight.
To run a computer program (casual usage, similar to 'run' or 'execute' a program).
新しく書いたスクリプトを走らしたらエラーが出た。
When I ran the new script, an error occurred.