Spelling Bee Acceptable
APL (Dyalog Unicode), 11 bytes



{⍵/⍨8&gt;≢∪⍵}¨


Takes input as a list of strings.

Explanation:

{⍵/⍨8&gt;≢∪⍵}¨
{       ⍵}¨ for each word
       ∪    take unique letters
    8&gt;≢     length less than 8 as a boolean (0 or 1)
 ⍵/⍨        repeat word that many times


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