wagtail
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a kind of bird – song bird – ground-feeding – insectivore (= feeds mostly on insects) – small, slender body (different species with different feather colours), small head, short, pointed beak (bill), pointed wings, slender, medium-sized legs with long claws, long flat tail; size: 6-9 inches long, weight: 15-25 grams; feeds on insects; lives for 2-5 years (one individual lived for 10 years); found in several parts of the world, mostly in Eurasia and Africa
The ‘willie wagtail’ of Australia looks like (resembles) a ‘true wagtail’, but it belongs to the ‘flycatchers’.

a white wagtail
The ‘white wagtail’ is the national bird of Latvia, a country in the Baltic region of North Europe.
The most interesting feature of the wagtail is the way it moves (wags) its tail up and down while walking and feeding on the insects on the ground!
(he) thought he had got a goldfinch, but it proved a wagtail [said of a man who married for money, but his wife turned out a flirt (‘flirt’ = a person who frequently changes sex partners or who frequently changes the friends of opposite sex; ‘goldfinch’ = a kind of bird)]
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