the cat that ate the canary

the cat that ate the canary

Happy, often in a selfsatisfied way. Someone who was very pleased—and often smug—was compared to a house cat that figured out a way to liberate a pet bird from its cage and enjoy the aftermath.
See also: ate, canary, cat, that
References in periodicals archive ?
They feel like the cat that ate the canary, sitting quietly in the corner hoping no one will notice.
A modest fellow, BP downplays the coup but a glint in the eye reminds one of the cat that ate the canary.