The state or quality of being doubtful; doubt; uncertainty.(noun)
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Use "doubtfulness" in a sentence
"I doubt that Michelle Obama was surprised or dismayed by the boos at the Nascar rally: it's not surprising that the national doubtfulness about first ladies and the strong, accomplished women who are coming to hold the role would emerge in boos from some of the Obama administration's fiercest opponents."
"It seemed to him that it had to do with the doubtfulness of whether or not the mortgagor will pay the debt."
"There has been evidence of such doubtfulness this week after initial claims for jobless benefits exceeded forecasts in the past four weeks."