unbiased, a. [unprejudiced], [impartial], unjaundiced, neutral, [disinterested].
unbidden, a. [unasked], uninvited; [spontaneous], [voluntary], volitional.
unblamable, a. [blameless], inculpable, irreprehensible, [innocent].
unblushing, a. [shameless], unabashed, [brazen-faced], [indecent], [immodest].
unbosom, v. [confess], [reveal], divulge.
unbounded, a. illimitable, [boundless], [unlimited], limitless, immeasurable, [vast], infinite, [immense].
unbreakable, a. infrangible; inviolable (said of a promise or vow).
unbreakableness, n. infrangibility; inviolability.
unbreathable, a. irrespirable.
unbridled, a. [unrestrained], uncurbed, uncontrolled, [licentious], [immoderate].