An Australian hawk cuckoo, Cuculus pallidus, with variable greyish or rufous plumage (often pale grey in the male); also (Australian) called brain-fever bird.
Origin
Late 19th century; earliest use found in Archibald James Campbell (b. 1853).
Definition of pallid cuckoo in US English:
pallid cuckoo
noun
An Australian hawk cuckoo, Cuculus pallidus, with variable greyish or rufous plumage (often pale grey in the male); also (Australian) called brain-fever bird.
Origin
Late 19th century; earliest use found in Archibald James Campbell (b. 1853).