#1 straightness n. (of hair) lack of a tendency to curl. wn
#2 straightness n. freedom from crooks or curves or bends or angles. wn
#3 straightness n. [directness] trueness of course toward a goal; "rivaling a hawk in directness of aim". wn
#4 straightness n. [good faith] having honest intentions; "he acted in good faith"; "doubt was expressed as to the good faith of the immigrants". wn
#5 straightness n. [heterosexuality, heterosexualism] a sexual attraction to (or sexual relations with) persons of the opposite sex. wn
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