The state or condition of being unflinching; steadfastness, resoluteness.(noun)
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Use "unflinchingness" in a sentence
"Before her landscape series, Ms. Jones created many expressionist self-portraits that lent an unflinchingness to her jagged-to-swirly mark-making, much of it with big oil-paint crayons."
"The hardened, suffering speakers in her recent fine story collection, Taking Pictures, use this tone; the grim damage of her Booker-winning The Gathering is energised by all that darkly comic unflinchingness."