Cold is an adjective in that context.
Cold is a noun and an adjective. Noun: I have a cold. Adjective: Expect cold weather.
So is an adverb in that example.
It depends. Noun: Give her a drink of water. We have a house on the water. The water is cold. Verb: Don't forget to water the flowers. Adjective: There's a hole in the water bucket. The pilot tried for a water landing.
Colder is an adjective. It's the comparative form of cold.
Cough is a verb because you can cough for example the man had to 'cough'.
What part of speech is the word freely in freely enjoying the water
Hydrophobia (the fear of water) is a noun.
The word lake is a noun. It is a stretch of water.
Cold is a noun and an adjective. Noun: I have a cold. Adjective: Expect cold weather.
In that usage, it would be an adverb.
part of speech