noun Any semi-solid or liquid substance; especially one that is sticky, gummy or slippery, unpleasant, and of vague or unknown composition, such as slime or semen.
I stepped in some goo and had a terrible time getting the sticky stuff off my shoes.
noun Excessive, showy sentimentality.
verb To apply goo to something.
They gooed their hair with some fragrant styling product.
noun A noise made by a baby trying to imitate speech.
The infant's goos and gahs were endearing.
verb To produce baby talk.
The baby gooed while daddy made sappy faces at it.