What is the meaning of Regex?

5-letter words containing

• 5-letter words containing a

• 5-letter words containing r

• 5-letter words containing e

• 5-letter words containing e

• 5-letter words containing k

5-letter words starting with

• 5-letter words starting with e

• 5-letter words starting with c

• 5-letter words starting with i

• 5-letter words starting with m

• 5-letter words starting with p

5-letter words in the middle

• 5-letter words in the middle u

• 5-letter words in the middle a

• 5-letter words in the middle e

• 5-letter words in the middle n

• 5-letter words in the middle r

5-letter words ending with

• 5-letter words ending with i

• 5-letter words ending with e

• 5-letter words ending with a

• 5-letter words ending with s

• 5-letter words ending with e

5-letter words excluding

• 5-letter words excluding i

• 5-letter words excluding e

• 5-letter words excluding c

• 5-letter words excluding s

• 5-letter words excluding u