'burst out' definitions:

Definition of 'burst out'

(from WordNet)
verb
Give sudden release to an expression; "We burst out laughing"; "'I hate you,' she burst out"
verb
Appear suddenly; "Spring popped up everywhere in the valley" [syn: pop out, burst out]
verb
Erupt or intensify suddenly; "Unrest erupted in the country"; "Tempers flared at the meeting"; "The crowd irrupted into a burst of patriotism" [syn: erupt, irrupt, flare up, flare, break open, burst out]