diff --git a/nifty5/library/__init__.py b/nifty5/library/__init__.py
index a3d08fdd58faf6d748efd49ff5d696e0da9bd31e..25bb9d9058d59e0bdc840dd0c59f753bfa517ede 100644
--- a/nifty5/library/__init__.py
+++ b/nifty5/library/__init__.py
@@ -1,10 +1,10 @@
 from .amplitude_model import make_amplitude_model
 from .apply_data import ApplyData
+from .gaussian_energy import GaussianEnergy
 from .los_response import LOSResponse
 from .nonlinear_wiener_filter_energy import NonlinearWienerFilterEnergy
-from .gaussian_energy import GaussianEnergy
 from .point_sources import PointSources
-from .poisson_log_likelihood import PoissonLogLikelihood
+from .poissonian_energy import PoissonianEnergy
 from .smooth_sky import make_smooth_mf_sky_model, make_smooth_sky_model
 from .wiener_filter_curvature import WienerFilterCurvature
 from .wiener_filter_energy import WienerFilterEnergy
diff --git a/nifty5/library/poisson_log_likelihood.py b/nifty5/library/poissonian_energy.py
similarity index 94%
rename from nifty5/library/poisson_log_likelihood.py
rename to nifty5/library/poissonian_energy.py
index 889e7bdbfa0e45ed94f39a4efabe1640776dc25b..e53db9da9649efe202a87d40f6c8ada68fbc3ede 100644
--- a/nifty5/library/poisson_log_likelihood.py
+++ b/nifty5/library/poissonian_energy.py
@@ -23,7 +23,7 @@ from ..operators.sandwich_operator import SandwichOperator
 from ..sugar import log, makeOp
 
 
-class PoissonLogLikelihood(Energy):
+class PoissonianEnergy(Energy):
     def __init__(self, lamb, d):
         """
         lamb: Sky model object
@@ -31,7 +31,7 @@ class PoissonLogLikelihood(Energy):
         value = 0.5 * s.vdot(s), i.e. a log-Gauss distribution with unit
         covariance
         """
-        super(PoissonLogLikelihood, self).__init__(lamb.position)
+        super(PoissonianEnergy, self).__init__(lamb.position)
         self._lamb = lamb
         self._d = d