unsuited (adj.) unsuitable (adj.) unsuccessful (adj.) unsubstantiated (adj.) unsubstantial (adj.) unsubsidized (adj.) unsubscribe (v.) unstudied (adj.) unstuck (adj.) unstrung (adj.) unstring (v.) unstressed (adj.) unstoppable (adj.) unstop (v.) unstinting (adj.) unstinted (adj.) unstick (v.) unsteady (adj.) unstack (v.) unstable (adj.)