I am looking for a word to describe a person who never really gets offended. Can it be described in one word?
Thick-skinned is a possibility:
thick-skinned - adjective
Someone who is thick-skinned does not appear to be easily hurt by criticism:
- You do need to be thick-skinned to survive as a politician here.
imperturbable: incapable of being upset or agitated; not easily excited; calm: imperturbable composure.
Unflappable is an adjective you may use:
- not likely to get worried, nervous, or angry even in difficult situations:
- She's totally unflappable - you have to be when working in such a high-pressure environment.
From The Free Dictionary
not easily worried or angered; relaxed and rather casual; calm
(As an aside, such a person can be infuriating.)
Phlegmatic is one of the "four temperaments" with the others being Melancholic, Sanguine, and Choleric From the concept of Four Humors of Greco-Roman medicine
Phlegmatic - adjective
not easily excited to action or display of emotion; apathetic; sluggish.
self-possessed, calm, or composed.
You say it never really gets offended. One that never gets offended could be imperturbable or thick-skinned, but in both cases, the word makes me think that they don't react at all.
Someone that does react, but is not offended (for example s/he may reply politely to deny an accusation of being born out of wedlock), I'd call a tolerant person.