I am here again for this week,how I love this particular contest.

The word is Maladaptation:-

• It is a 13 letter word,
• Starts with letter "M"
• Part name: Yes, "adaptation" functions as a noun describing a specific aspect within an organism or system.
• Too much of a certain thing :-"maladaptation" implies an attempt to adapt has become excessive and harmful.
• It can be harming: Yes, maladaptation can have negative consequences, making it harmful.

♥️♥️
@tripple-e