Field vocabulary
Ornithology dictionary
Clear definitions, word origins where sourced, and links between related birding concepts.
Featured terms
Catalog entries
12 entries
Altricial
nest-bound
Describes young birds that hatch relatively undeveloped, often naked or lightly downed, and depend on parents for warmth, feeding, and protection in the nest.
Brood parasitism
nest parasitism
A reproductive strategy in which a bird lays eggs in another bird’s nest, leaving the host to provide care.
Clutch
egg set
The complete set of eggs laid by one female during a single nesting attempt, usually before she begins continuous incubation or brooding.
Crepuscular
twilight-active
Active chiefly during twilight around dawn or dusk rather than in full daylight or complete darkness.
Dimorphism
sexual dimorphism
A consistent difference in appearance between two forms of one species, often between adult males and females.
Diurnal
day-active
Active mainly during daylight hours, a pattern followed by many songbirds, raptors, and waterbirds.