The phrase "to burst out" means to suddenly express strong emotions or feelings, often in a loud and uncontrolled manner. It can also refer to an unexpected or sudden occurrence that is difficult to contain or control.
Sometimes people have trouble following me when I talk because the explosion of thoughts bursts out of my mouth at bullet - fast speed. (housegoeshome.com)
You won't be able to resist the urge to bursting out laughing at these funny pick up lines. (myintimcity.com)
The video is so clear and colors are just bursting out in this film. (mediamikes.com)