diff --git a/library/psa_crypto.c b/library/psa_crypto.c
index 10c7d1e..f129733 100644
--- a/library/psa_crypto.c
+++ b/library/psa_crypto.c
@@ -5133,7 +5133,7 @@
     if( status != PSA_SUCCESS )
         return( status );
     /* Breaking up a request into smaller chunks is currently not supported
-     * for the extrernal RNG interface. */
+     * for the external RNG interface. */
     if( output_length != output_size )
         return( PSA_ERROR_INSUFFICIENT_ENTROPY );
     return( PSA_SUCCESS );