What is the meaning of Non-standard?

5-letter words containing

• 5-letter words containing u

• 5-letter words containing s

• 5-letter words containing n

• 5-letter words containing i

• 5-letter words containing v

5-letter words starting with

• 5-letter words starting with n

• 5-letter words starting with a

• 5-letter words starting with i

• 5-letter words starting with t

• 5-letter words starting with e

5-letter words in the middle

• 5-letter words in the middle f

• 5-letter words in the middle c

• 5-letter words in the middle a

• 5-letter words in the middle n

• 5-letter words in the middle g

5-letter words ending with

• 5-letter words ending with a

• 5-letter words ending with a

• 5-letter words ending with c

• 5-letter words ending with e

• 5-letter words ending with e

5-letter words excluding

• 5-letter words excluding i

• 5-letter words excluding a

• 5-letter words excluding r

• 5-letter words excluding e

• 5-letter words excluding c