Noah Webster
Doubtful
DOUBTFUL, adjective
1. Dubious; not settled in opinion; undetermined; wavering; hesitating; applied to persons; as, we are doubtful of a fact, or of the propriety of a measure.
2. Dubious; ambiguous; not clear in its meaning; as a doubtful expression.
3. Admitting of doubt; not obvious, clear or certain; questionable; not decided; as a doubtful case; a doubtful proposition; it is doubtful what will be the event of the war.
4. Of uncertain issue.
We have sustained one day in doubtful fight.
5. Not secure; suspicious; as, we cast a doubtful eye.
6. Not confident; not without fear; indicating doubt.
With doubtful feet, and wavering resolution.
7. Not certain or defined; as a doubtful hue.