jacamar, any of 18 species of tropical American birds that constitute the family Galbulidae (order Piciformes). The jacamar has a glittering body, tapered from large head to, in most species, a long, graduated tail; some have square tails. Most are iridescently blue, green, or bronze on back and breast; males are white-throated, females brown-throated. The commonest species is the rufous-tailed jacamar (Galbula ruficauda), 25 cm (10 inches) long, found from southern Mexico to Argentina.
Jacamars sit, with the long, sharp bill tilted up, in trees along forest streams, then dash on whirring wings after a butterfly or dragonfly, which they catch with an audible snap of the bill and pound on the perch before eating. The egg chamber is dug into a bank or level ground.