Thunderbird \Thun"der*bird`\, n. (Zo["o]l.) An Australian insectivorous singing bird ({Pachycephala gutturalis}). The male is conspicuously marked with black and yellow, and has a black crescent on the breast. Called also {white-throated thickhead}, {orange-breasted thrust}, {black-crowned thrush}, {guttural thrush}, and {black-breasted flycatcher}.