One word with many meanings is a homograph.
Ambiguous. Heteronym
a homophone
These are homonyms or homophones.
When a word like "bass" has two different meanings and pronunciations, it is known as a homograph. Homographs are words that are spelled the same but have different meanings.
The word has evolved to have many different meanings, and it can have either a positive or negative connotation
A word that has another word derived from it is called an Eponym. The two words will usually have different meanings.
The word you are looking for is "pun." A pun is a play on words that relies on a word's multiple meanings or on two words that sound similar but have different meanings.
they have different meanings
It has many different meanings or maybe it is informal. Smoothie has different synonyms but it is the original known word
There are many different meanings of heartache [metaphorical or not] such as:afflictionagonybitternessbroken heartdejectiondepressiondespairdespondencydistressdolorgriefheartbreakheavy hearthurtingmiserypangremorsesadnesssufferingtormenttortureEnjoy.
its connotation
Yes it is. It has different meanings.
A word that is spelled the same with two different meanings is called a homonym.