Adding suffix "ian/an" to proper noun?

Question

Hello. One of my ESL students asked me if there is a term for when you add "ian/an" to a proper noun like Canada - Canadian, Brazil - Brazilian, Chicago - Chicagoan? What is this called?

Answer 1

Below are links with information on suffixes ian and an.  There is not a "term" for it other than they are suffixes.  

SUFFIX An AFFIX added at the end of a WORD, BASE, or ROOT to form a new word: -ness added to dark to form darkness; -al added to leg to form legal. Two distinctions are usually made: (1) Between a derivational suffix proper, such as -ness and -al, which creates derivative words, and an inflectional ending, such as -s added to form the plurals of nouns, which changes the inflection of a word. (2) Between a productive suffix, which actively forms words (-ness: darkness, newness, quaintness, wordiness) and a non-productive suffix, which does not (-ledge: knowledge).

-ian, an

Noun: related to, one that is

pedestrian : a person who walks

ped + estr + ian

human: a person

hum + an

Answer 2

The adjectives for countries are called "adjectives of nationality." I'd refer to the process as "forming adjectives of nationality." I've never heard another term for it.