One who's loyal to a fault Crossword Clue

 The crossword clue "One who's loyal to a fault" can be DOGMATIC.

The word "dogmatic" means "adhering to rigid principles or beliefs". It can also mean "unwilling to admit the possibility of error".

In the context of the crossword clue, the word "dogmatic" is likely being used to describe someone who is loyal to a fault. This means that they are so loyal to their beliefs or principles that they are unwilling to consider any other possibility.

Here are some other possible answers for the crossword clue "One who's loyal to a fault":

IDEOLOGICAL

CONSERVATIVE

TRADITIONALIST

UNCOMPROMISING

UNFORGIVING

The specific answer that is correct will depend on the context of the crossword puzzle.