What is the meaning of Equational_classes?

5-letter words containing

• 5-letter words containing r

• 5-letter words containing a

• 5-letter words containing g

• 5-letter words containing s

• 5-letter words containing e

5-letter words starting with

• 5-letter words starting with u

• 5-letter words starting with x

• 5-letter words starting with c

• 5-letter words starting with n

• 5-letter words starting with c

5-letter words in the middle

• 5-letter words in the middle l

• 5-letter words in the middle e

• 5-letter words in the middle i

• 5-letter words in the middle n

• 5-letter words in the middle i

5-letter words ending with

• 5-letter words ending with a

• 5-letter words ending with t

• 5-letter words ending with n

• 5-letter words ending with e

• 5-letter words ending with i

5-letter words excluding

• 5-letter words excluding a

• 5-letter words excluding o

• 5-letter words excluding i

• 5-letter words excluding r

• 5-letter words excluding b