As adjectives the difference between faggiest and saggiest
is that faggiest is (faggy) while saggiest is (saggy).
faggiest
English
Adjective
(head)
(faggy) faggy
English
Adjective
(er)
(pejorative, informal) Effeminate; homosexual; gay
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saggiest
English
Adjective
(head)
(saggy)
saggy
English
Adjective
(er)
Baggy or loose-fitting.
That sinks or droops from wear or its own weight.