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The term spectral temperature is occasionally used in astrophysics, clearly implying a temperature determination based upon an object's spectrum. For stellar temperature determination, a star's spectral class and spectral type are based upon spectral features that are temperature-dependent, and I expect a temperature evident from a star's classification is what is generally meant. However, likely all methods of determining a distant body's temperature are based upon its spectrum in some way. Active galactic nuclei also have spectral signatures providing information about temperatures of various parts.
In general, absorption lines imply electromagnetic radiation (EMR) from multiple layers that are at different temperatures, clearly the nearer ones sufficiently optically thin to allow that to happen. This provides information regarding the temperatures of the different layers, and a cited value is for just one of these layers.
Among the other temperature-determination methods, a black-body spectrum has an associated temperature, and spectra close to black-body indicate something close to that temperature, a brightness temperature is effectively based on one sample from the spectrum, a color temperature is based upon the ratio of two, and an effective temperature is based upon the total energy per the full spectral energy distribution (SED).