IPA: /əˌfɔːdəˈbɪləti/
KK: /əˈfɔrdəˌbɪlɪti/
The degree to which something can be bought or paid for without causing financial strain.
The affordability of housing in the city has become a major concern for residents.
Affordability is formed from "afford" (from Old English "forðian", meaning to provide or to give) and the suffix "-ability" (meaning the quality of being able to). The word "affordability" refers to the quality of being able to provide or give something, particularly in terms of financial means.
Think of 'providing' ('afford') something and the quality of being 'able' ('-ability') to do so — that's what affordability means.