diff --git a/include/mbedtls/pk.h b/include/mbedtls/pk.h
index f7fa4d3..36fdea5 100644
--- a/include/mbedtls/pk.h
+++ b/include/mbedtls/pk.h
@@ -475,7 +475,7 @@
  *
  * \return          Maximum size in bytes of a signature made with this key.
  */
-size_t mbedtls_pk_signature_size( const mbedtls_pk_context *ctx );
+size_t mbedtls_pk_get_signature_size( const mbedtls_pk_context *ctx );
 
 /**
  * \brief           Decrypt message (including padding if relevant).