diff --git a/pygmt/base_plotting.py b/pygmt/base_plotting.py
index f18b1ffd454..c7c85813cdf 100644
--- a/pygmt/base_plotting.py
+++ b/pygmt/base_plotting.py
@@ -266,9 +266,9 @@ def grdcontour(self, grid, **kwargs):
         limit : str or list of 2 ints
             Do no draw contours below `low` or above `high`, specify as string
             ``'[low]/[high]'``  or list ``[low,high]``.
-        cut : string or int
+        cut : str or int
             Do not draw contours with less than `cut` number of points.
-        resample : string or int
+        resample : str or int
             Resample smoothing factor.
         {J}
         {R}