diff --git a/cryptography/hazmat/backends/interfaces.py b/cryptography/hazmat/backends/interfaces.py
index 630e707..b867f26 100644
--- a/cryptography/hazmat/backends/interfaces.py
+++ b/cryptography/hazmat/backends/interfaces.py
@@ -85,8 +85,8 @@
 
 class RSABackend(six.with_metaclass(abc.ABCMeta)):
     @abc.abstractmethod
-    def generate_rsa_private_key(self, public_exponent, bit_length):
+    def generate_rsa_private_key(self, public_exponent, key_size):
         """
         Generate an RSAPrivateKey instance with public_exponent and a modulus
-        of bit_length bits.
+        of key_size bits.
         """
diff --git a/docs/hazmat/backends/interfaces.rst b/docs/hazmat/backends/interfaces.rst
index 444ecb4..db68a64 100644
--- a/docs/hazmat/backends/interfaces.rst
+++ b/docs/hazmat/backends/interfaces.rst
@@ -199,12 +199,12 @@
 
     A backend with methods for using RSA.
 
-    .. method:: generate_rsa_private_key(public_exponent, bit_length)
+    .. method:: generate_rsa_private_key(public_exponent, key_size)
 
         :param int public_exponent: The public exponent of the new key.
             Often one of the small Fermat primes 3, 5, 17, 257 or 65537.
 
-        :param int bit_length: The length in bits of the modulus. Should be
+        :param int key_size: The length in bits of the modulus. Should be
             at least 2048.
 
         :return: A new instance of a