In an incautious manner; with a lack of caution.(adverb)
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Use "incautiously" in a sentence
"Bob, impressing upon him all my arrangements, in case of contingencies requiring an alteration in my original plan; for, as soon as we were fairly at work, everything would have to be done, as far as possible, in absolute silence, and I did not wish to leave any explanations for a moment when, perhaps, a single word incautiously uttered might lead to our betrayal."
"Immediately the mutiny had been put down Jack Stilwell had stolen away and rejoined the soldiers forward; and although there was much wonder among the men as to how the affair had been discovered, none suspected him of having betrayed them, and believed that the officers must have been warned by some word incautiously let drop in their hearing."
"It has been used, for example, against those who refer too incautiously to the civilian carnage visited upon Gaza and Lebanon by the Israeli Defence Forces."