What is the meaning of Regular_language?

5-letter words containing

• 5-letter words containing p

• 5-letter words containing b

• 5-letter words containing l

• 5-letter words containing e

• 5-letter words containing o

5-letter words starting with

• 5-letter words starting with i

• 5-letter words starting with t

• 5-letter words starting with e

• 5-letter words starting with u

• 5-letter words starting with z

5-letter words in the middle

• 5-letter words in the middle l

• 5-letter words in the middle t

• 5-letter words in the middle t

• 5-letter words in the middle k

• 5-letter words in the middle l

5-letter words ending with

• 5-letter words ending with o

• 5-letter words ending with d

• 5-letter words ending with e

• 5-letter words ending with i

• 5-letter words ending with e

5-letter words excluding

• 5-letter words excluding c

• 5-letter words excluding l

• 5-letter words excluding e

• 5-letter words excluding r

• 5-letter words excluding a