diff --git a/tupak/gw/waveform_generator.py b/tupak/gw/waveform_generator.py
index 663ee7a2321edf7f1645e231f09f3674b4e093ea..cb4a1f2224ec40015587dab9696dc7c3da8f8bbb 100644
--- a/tupak/gw/waveform_generator.py
+++ b/tupak/gw/waveform_generator.py
@@ -28,8 +28,9 @@ class WaveformGenerator(object):
         waveform generator
     non_standard_sampling_parameter_keys: list
         List of parameter name for *non-standard* sampling parameters.
-    fixed_arguments: dict
-        A dictionary of fixed keyword arguments
+    waveform_arguments: dict
+        A dictionary of fixed keyword arguments to pass to either
+        `frequency_domain_source_model` or `time_domain_source_model`.
 
     Note: the arguments of frequency_domain_source_model (except the first,
     which is the frequencies at which to compute the strain) will be added to
@@ -39,7 +40,8 @@ class WaveformGenerator(object):
 
     def __init__(self, time_duration, sampling_frequency, frequency_domain_source_model=None,
                  time_domain_source_model=None, parameters=None, parameter_conversion=None,
-                 non_standard_sampling_parameter_keys=None, fixed_arguments={}):
+                 non_standard_sampling_parameter_keys=None,
+                 waveform_arguments=dict()):
         self.time_duration = time_duration
         self.sampling_frequency = sampling_frequency
         self.frequency_domain_source_model = frequency_domain_source_model
@@ -49,11 +51,11 @@ class WaveformGenerator(object):
         self.parameter_conversion = parameter_conversion
         self.non_standard_sampling_parameter_keys = non_standard_sampling_parameter_keys
         self.parameters = parameters
-        self.fixed_arguments = fixed_arguments
+        self.waveform_arguments = waveform_arguments
         self.__frequency_array_updated = False
         self.__time_array_updated = False
         self.__full_source_model_keyword_arguments = {}
-        self.__full_source_model_keyword_arguments.update(fixed_arguments)
+        self.__full_source_model_keyword_arguments.update(waveform_arguments)
 
     def frequency_domain_strain(self):
         """ Wrapper to source_model """