Dictionary

Any semi-solid or liquid substance; especially one that is sticky, gummy or slippery; frequently of vague or unknown composition, slime or a bodily fluid.

Example: I stepped in some goo and had a terrible time getting the sticky stuff off my shoes.

Excessive, showy sentimentality.

To apply goo to something.

Example: They gooed their hair with some fragrant styling product.

An example of baby talk.

Example: The infant's goos and gahs were endearing.

To produce baby talk.

Example: The baby gooed while daddy made sappy faces at it.