To learn this word, divide it as super+flow i.e when there is large(super) flow of water, it becomes EXCESSIVE
Meanings of Superfluous:
1. being more than is sufficient or required; excessive.
2.unnecessary or needless.
3.Obsolete . possessing or spending more than enough
Sentence Examples for Superfluous:
1. The existence of the human data, however, renders the animal data superfluous.
2. To the dozen medics around the table, the point that the doctor was making seemed almost superfluous.
3. Many programming languages work by eliminating information from the file that the program deems superfluous.