Too much and Unheard-of

Too much adverb - More than necessary.

Unheard-of and too much are semantically related. In some cases you can use "Unheard-of" instead an adjective phrase "Too much".

Unheard-of adjective - Not known or experienced before.

Too much and unheard-of are semantically related. Sometimes you can use "Too much" instead an adjective phrase "Unheard-of".