Truly

21 clues
Quite!
Indeed!
Really!
In fact
Sincerely
For real?
Genuinely
____verily
Honest(ly)
Faithfully
No fooling?
No kidding!?
Sign-off word
Without a doubt!
Word in a letter
Without question!
Emphatic agreement
Honest-to-goodness
I kid you not!
As a matter of fact
''I'm not kidding!''

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