معنی کلمه pick up

grasp and lift; gather, obtain; hurry up, gain speed;

improve; straighten, tidy (Colloquial); approach someone with an offer of romantic involvement (Informal);

resume after an intermission; buy, get (e.g.: "We are out of milk, on your way home from work can you pick up a carton of milk?")

lifted, raised; obtained, got; gathered; approached with an offer for romantic involvement (Informal); straightened, tidied (Colloquial)

The phone rang and I picked it up.

That leaves us with an easy rule to follow: When you need a noun or adjective, stick with the single-word pickup.

When you're describing an action, use the two-word pick up as a verb. With that distinction in mind, you'll find that applying the correct version is easy.