Unscramble Irnfs

What is the meaning of word irnfs unscrambled?

What 5 letter words can be made from letters I R N F S:

1. firns - Definition of firns

Make more words by adding or removing letters

How many 4 letter words can you make from letters I R N F S?

1. fins - Definition of fins

2. firn - Definition of firn

3. firs - Definition of firs

4. rifs - Definition of rifs

5. rins - Definition of rins

Which 4 letter words can be made by removing one letter and unscrambling the remaining letters?
1) Removing the letter I and unscrambling rnfs
2) Removing the letter R and unscrambling infs
3) Removing the letter N and unscrambling irfs
4) Removing the letter F and unscrambling irns
5) Removing the letter S and unscrambling irnf

More anagrams containing the letters I R N F S
irnsf irsfn nifsr snrif