GHAYRUN-Lexicography
Ghayrun: Other, another, different one, except, save, without, not, other than,
Act of altering, changing.
Ghayr (Ghaar): To be jealous of (someone) for.
Ghayyara: To alter change, substitute, change for the worse
Ghaayara: To exchange, barter (with another). Differ mutually .
Ghayratun: Indignation over what is wrong.
(Wortabet)
Ghayr: Diminution (F.Steingass)
Ghayr: To corrupt, Else, lie, Not at all
Ghiyar: Changes of fortune
Ghiyaar: Mark in dress distinguishing muslims.
(J.G.Hava)
Ghayrun: But This word has been used at 113 places in the Quran in different meanings in the context. It has mainly been used for:

i. Negation:
ii. Like "Illaa" as Exception:
iii. Partial Negation, while the original remains the same:
iv. Total Negation:
(Lughaatul Quran, Muhammad Abdur-Rashid Nomani)
Mutaghayyir": Changed pale due to disease
(Ferozul-Lughaat)
Ghayr: Negation of (i) a thing and / or (ii) its qualities.

It may be used as "Illaa" (except, save).
But it is not the synonym of `different'. The word "Ghayr" is more common and comprehensive. (Mifridatul Quran, Imam Raghib Isfahani).

It appears that in this verse (1-7) Ghayr (Negation) has been used for a complete exclusion of all those who were angered upon. Abdullah Yusuf Ali is of the opinion that "The negative 'Ghayr" should be construed as applying not to the way, but as describing men protected from two dangers by Allah's Grace."

For different usage, Al-Muajamul Mufahras, Muhammad Fawad Abdul Baqi.