Biology. Of an organism: freely mobile, not sessile; not fixed to or enclosed within a substrate. Also (now more commonly): living independently…

Of an animal, esp. a bird: able to feed itself soon after hatching or birth; = precocial, adj. Also: characterized by such behaviour.

Zoology. Chiefly Ornithology = precocial, adj.

Of an animal, esp. a bird: able to move about and feed independently soon after hatching or birth; having young which are able to do this; = nidif…