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We report a detailed analysis of the FASSST rotational spectrum of the S(CN)$2$ molecule, which has been recorded almost continuously from 110 to 375 GHz. S(CN)$2$ is of $C2v$ symmetry, is characterised by a low frequency bending mode of 120-130 cm$\mathrm{<mrow\; data-mjx-texclass="ORD">-1</mrow>}$, and has four other normal modes with frequencies of less than 500 cm$\mathrm{<mrow\; data-mjx-texclass="ORD">-1</mrow>}$. Only cm-wave transitions in the ground state of several isotopomers,} {\bf 19a}, 1428 (1964)}$\mathrm{<mrow\; data-mjx-texclass="ORD">,</mrow>}$} {\bf 43}, 3423 (1965)}$\mathrm{<mrow\; data-mjx-texclass="ORD">,</mrow>}$} {\bf 124}, 481 (1987)} and some transitions in the first excited bending state have previously been observed. \vspace{0.2cm} Rotational transitions in first excited states of all five lowest frequency normal have now been assigned, as well as in the bending progression up to $v=5$, and in some combination states. The use of the efficient, newly written $AABS$ package for Analysis and Assignment of Broadband Spectra allowed several thousand lines to be added also to the datasets for the ground states of the parent, and the $\mathrm{<mrow\; data-mjx-texclass="ORD">34</mrow>}$S isotopomers. The total number of lines measured in the FASSST spectrum of S(CN)$2$ is well over 10000. Octic level spectroscopic constants have been derived for the studied states, and their vibrational dependence will be discussed. Vibrational assignment was confirmed by means of $abinitio$ inertial defect calculations.