\definefont[BigOne][SerifBold at 30pt]

\definedescription[whatever][headstyle=\BigOne, width=2em, align=right]

\starttext

    \startwhatever{bla}
        \input ward
    \stopwhatever

    \startwhatever{bla}
        \input ward
    \stopwhatever

    \noindent \ruledvtop{\hsize 1cm \BigOne bla}\input ward

\stoptext
