  We propose to utilize the average jet charge weighted single-spin asymmetry
$A_e^{bQ}$ in the neutral current DIS scattering with one $b$-tagged jet
produced at the EIC to probe the $Zb\bar{b}$ interactions. This novel
observable is sensitive to the axial-vector component of the $Zb\bar{b}$
coupling and is complementary to the single-spin asymmetry measurement at the
EIC and the $gg\to Zh$ cross section measurement at the HL-LHC in the
determination of the $Zb\bar{b}$ couplings. We show that the apparent
degeneracy of the $Zb\bar{b}$ couplings, implied by the LEP and SLC precision
electroweak data, can be broken by the $A_e^{bQ}$ measurement at the EIC. With
a large enough integrated luminosity collected at the EIC, the measurement of
$A_e^{bQ}$ could also resolve the long-standing discrepancy of $A_{\rm FB}^b$
at the LEP, strongly dependent on the $b$-tagging efficiency.
