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The pure rotational spectrum of HZnCH$3$ has been observed in its ground electronic state (\ {X} $\mathrm{<mrow\; data-mjx-texclass="ORD">1</mrow>}A1$) using both direct absorption and Fourier transform microwave techniques in the frequency range 18-516 GHz. Twelve rotational transitions of this symmetric top species were recorded in K-ladders up to K = 7. The molecule was synthesized from Zn(CH$3$)$2$ in an AC discharge and also from Zn (vapor) + CH$4$ with a DC discharge. From measurements of the spectra of various isotopic species ($\mathrm{<mrow\; data-mjx-texclass="ORD">66</mrow>}$Zn, $\mathrm{<mrow\; data-mjx-texclass="ORD">67</mrow>}$Zn, $\mathrm{<mrow\; data-mjx-texclass="ORD">68</mrow>}$Zn, $\mathrm{<mrow\; data-mjx-texclass="ORD">13</mrow>}$C, and $2$H), an accurate structure has been determined. The H-C-H bond angle was found to be $108.7irc$, slightly smaller than that in ZnCH$3$ or CH$4$. In addition, nuclear spin-rotation (I $.$ J) interactions with the methyl hydrogen nuclei and electric quadrupole coupling from the $\mathrm{<mrow\; data-mjx-texclass="ORD">67</mrow>}$Zn nucleus were resolved in the FTMW spectrum. From these data, hyperfine parameters have been established. The value of eqQ = -109.125(11) MHz indicates that the bonds to zinc are primarily covalent. Detection of this species, especially via the Zn + CH$4$ pathway, is a good indication of the ability of metal atoms to insert into C-H bonds.