insuppressible

"Vicar has his butter fra Brown's by rights," said the insuppressible servant-woman.

At that, in an insuppressible gush of happiness I laughed out with him, like a flageolet in a concourse of bassoons.

Kid was a witty man, usually overflowing with innocent mirth; even in sight of the gallows his humor was insuppressible.

Insuppressible, in-sup-pres′i-bl, adj. not to be suppressed or concealed.