My cat does this as well when a bird is close by.....they think they are going native with the lingo. Unless he is taking a course on the internet while I am out, my bird is just pretending to speak beak talk.
acorn - fruit of the oak tree: a smooth thin-walled nut in a woody cup-shaped base. acorn cup, cupule - cup-shaped structure of hardened bracts at the base of an acorn. oak tree, oak - a deciduous tree of the genus Quercus; has acorns and lobed leaves; great oaks grow from little acorns. fruit - the ripened reproductive body of a seed plant.
What Type of Tree Makes an Acorn? Only trees in the Quercus genus produce acorns. Watch a squirrel or chipmunk forage for food and no doubt a cache of acorns will appear. Acorns provide food for various wildlife, or they would otherwise litter the forest floor and rot since they are too heavy to disperse via wind. Instead, foraging animals scatter the seed and help to propagate the next generation of acorn-bearing trees.