LBJ

Little Brown Job. Describes many birds which are small, brown and otherwise not compelling.
Found on http://earthdesign.ca/dict.html

LBJ

a Little Brown Job. A large number of birds are small, brown and drab, and they all look almost exactly like at least a number of other species. Female or immature birds are quite likely to be LBJs, and identification can be tricky even for the experts.
Found on http://birding101.co.za/newbirder/birding-terms/

LBJ

Little brown job, small bird of bland colouration seen so briefly that a positive ID is not possible. See BVD.
Found on https://www.sciencebase.com/science-blog/birding-glossary.html
No exact match found