The act of making a guess; estimate or prediction; foresight(noun)
Present participle of guess.(verb)
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Use "guessing" in a sentence
"After what seemed like the longest gestation period ever known to man and over 24 hours of teasing her Twitter fans with a name guessing game involving the initial M it wasn't fun, just tedious, the twin's names have FINALLY been announced."
"The cost of password guessing is constantly going down, and the value of the data depends on the data."
"Today is their “Official Soft Opening” which I’m guessing is code for “don’t blame us if everything isn’t perfect”."