Unscramble Refdidths

What is the meaning of word refdidths unscrambled?

What 9 letter words can be made from letters R E F D I D T H S:

Make more words by adding or removing letters

How many 8 letter words can you make from letters R E F D I D T H S?

1. redshift - Definition of redshift

Which 8 letter words can be made by removing one letter and unscrambling the remaining letters?
1) Removing the letter R and unscrambling efdidths
2) Removing the letter E and unscrambling rfdidths
3) Removing the letter F and unscrambling redidths
4) Removing the letter D and unscrambling refidths
5) Removing the letter I and unscrambling refddths
6) Removing the letter D and unscrambling refdiths
7) Removing the letter T and unscrambling refdidhs
8) Removing the letter H and unscrambling refdidts
9) Removing the letter S and unscrambling refdidth

More anagrams containing the letters R E F D I D T H S
refdidtsh refdihdst dhstfired dshifrdet