Hard-hearted and One and only

Hard-hearted adjective - Having or showing a lack of sympathy or tender feelings.

One and only and hard-hearted are semantically related. In some cases you can use "One and only" instead an adjective phrase "Hard-hearted".

One and only adjective - Eminent beyond or above comparison.

Hard-hearted and one and only are semantically related. Sometimes you can use "Hard-hearted" instead an adjective phrase "One and only".