Meaning of the word "running in" in English

What does "running in" mean in English? Explore the meaning, pronunciation, and specific usage of this word with Lingoland.

running in

US /ˈrʌnɪŋ ɪn/
UK /ˈrʌnɪŋ ɪn/

Phrasal Verb

1.

to break in a new engine or vehicle by driving it carefully at moderate speeds for a period of time

Example:
•
You need to spend some time running in the new car before driving it at high speeds.
•
The mechanic advised me to run in the engine for the first 500 miles.
2.

to enter a place quickly or unexpectedly

Example:
•
The children came running in from the garden when it started to rain.
•
He suddenly ran in and announced the good news.