Call Up

1. To be chosen to take part in a military mission.

Examples: Back in the day, men were randomly called up and obligated to go fight in a war.
When you join the military, you could get called up to go overseas for a couple of years.

2. To telephone someone.

Examples: I miss being able to call up my grandma and listen to her funny stories.
I want to talk to someone, but there is no one to call up.

See our complete list of English phrasal verbs.