the only thing

:  unquestionably the best :  peerless

:  alone in a class or category :  sole

:  having no brother or sister

:  as a single fact or instance and nothing more or different :  merely

:  solely, exclusively

:  at the very least

:  with the restriction that :  but

:  and yet :  however

:  were it not that :  except

:  an object or entity not precisely designated or capable of being designated

:  an inanimate object distinguished from a living being

:  a separate and distinct individual quality, fact, idea, or usually entity