THICKHEAD
thickhead, whistler
(noun) Australian and southeastern Asian birds with a melodious whistling call
Source: WordNet® 3.1
Etymology
Noun
thickhead (plural thickheads)
Someone stupid.
Any of several species of Australian songbirds of the genus Pachycephala.
Synonyms
• See also idiot
Source: Wiktionary
Thick"head`, n.
1. A thick-headed or stupid person. [Colloq.]
2. (Zoรถl.)
Definition: Any one of several species of Australian singing birds of the
genus Pachycephala. The males of some of the species are bright-
colored. Some of the species are popularly called thrushes.
Source: Webster’s Unabridged Dictionary 1913 Edition