diff --git a/docs/sphinx/source/user_guide/nomenclature.rst b/docs/sphinx/source/user_guide/nomenclature.rst
index a89da06cbf..180f0a298f 100644
--- a/docs/sphinx/source/user_guide/nomenclature.rst
+++ b/docs/sphinx/source/user_guide/nomenclature.rst
@@ -142,6 +142,13 @@ There is a convention on consistent variable names throughout the library:
     solar_zenith
         Zenith angle of the sun in degrees
 
+    spectra
+    spectra_components
+        Spectral irradiance (components) [Wm⁻²nm⁻¹]. The amount of energy
+        incident on a unit area per unit time and per unit
+        wavelength. As with broadband irradiance, global spectral irradiance
+        is composed of direct and diffuse components.
+    
     surface_azimuth
         Azimuth angle of the surface
 
diff --git a/docs/sphinx/source/whatsnew/v0.11.2.rst b/docs/sphinx/source/whatsnew/v0.11.2.rst
index f3b1ec338a..a07f4bf43d 100644
--- a/docs/sphinx/source/whatsnew/v0.11.2.rst
+++ b/docs/sphinx/source/whatsnew/v0.11.2.rst
@@ -33,6 +33,10 @@ Documentation
   page, using the sphinx glossary directive. (:issue:`1421`, :pull:`2234`)
 * Explained how to write docstrings for new functions in :ref:`example-docstring`
   (:discussion:`2081`, :pull:`2254`)
+* Added the following variables to the :ref:`nomenclature` page:
+
+  - `spectra` and `spectra_components` (:issue:`2150`, :pull:`2264`)
+
 
 Testing
 ~~~~~~~
diff --git a/pvlib/spectrum/irradiance.py b/pvlib/spectrum/irradiance.py
index cb3e5e1ddb..14b2da27ba 100644
--- a/pvlib/spectrum/irradiance.py
+++ b/pvlib/spectrum/irradiance.py
@@ -189,7 +189,8 @@ def average_photon_energy(spectra):
     ----------
     spectra : pandas.Series or pandas.DataFrame
 
-        Spectral irradiance, must be positive. [Wm⁻²nm⁻¹]
+        Spectral irradiance, must be positive [Wm⁻²nm⁻¹].
+        See :term:`spectra`.
 
         A single spectrum must be a :py:class:`pandas.Series` with wavelength
         [nm] as the index, while multiple spectra must be rows in a
diff --git a/pvlib/spectrum/spectrl2.py b/pvlib/spectrum/spectrl2.py
index b022d79371..38739efff3 100644
--- a/pvlib/spectrum/spectrl2.py
+++ b/pvlib/spectrum/spectrl2.py
@@ -228,10 +228,11 @@ def spectrl2(apparent_zenith, aoi, surface_tilt, ground_albedo,
     Returns
     -------
     spectra_components : dict
-        A dict of arrays.  With the exception of `wavelength`, which has length
+        A dict of arrays. With the exception of `wavelength`, which has length
         122, each array has shape (122, N) where N is the length of the
         input ``apparent_zenith``.  All values are spectral irradiance
         with units Wm⁻²nm⁻¹, except for `wavelength`, which is in nanometers.
+        See :term:`spectra_components`.
 
         * wavelength
         * dni_extra