diff --git a/pandas/core/series.py b/pandas/core/series.py
index bfe9969daaa8e..040fcf392733b 100644
--- a/pandas/core/series.py
+++ b/pandas/core/series.py
@@ -23,6 +23,7 @@
 from pandas._config import get_option
 
 from pandas._libs import lib, properties, reshape, tslibs
+from pandas._libs.index import validate_numeric_casting
 from pandas._typing import Label
 from pandas.compat.numpy import function as nv
 from pandas.util._decorators import Appender, Substitution
@@ -1022,7 +1023,7 @@ def __setitem__(self, key, value):
     def _set_with_engine(self, key, value):
         # fails with AttributeError for IntervalIndex
         loc = self.index._engine.get_loc(key)
-        libindex.validate_numeric_casting(self.dtype, value)
+        validate_numeric_casting(self.dtype, value)
         self._values[loc] = value
 
     def _set_with(self, key, value):
@@ -1105,7 +1106,7 @@ def _set_value(self, label, value, takeable: bool = False):
                 self._values[label] = value
             else:
                 loc = self.index.get_loc(label)
-                libindex.validate_numeric_casting(self.dtype, value)
+                validate_numeric_casting(self.dtype, value)
                 self._values[loc] = value
         except KeyError:
 
diff --git a/pandas/tests/dtypes/test_common.py b/pandas/tests/dtypes/test_common.py
index 097e83d93ee71..4c917b9bb42d2 100644
--- a/pandas/tests/dtypes/test_common.py
+++ b/pandas/tests/dtypes/test_common.py
@@ -675,6 +675,8 @@ def test__get_dtype(input_param, result):
 )
 def test__get_dtype_fails(input_param, expected_error_message):
     # python objects
+    # 2020-02-02 npdev changed error message
+    expected_error_message += f"|Cannot interpret '{input_param}' as a data type"
     with pytest.raises(TypeError, match=expected_error_message):
         com._get_dtype(input_param)
 
diff --git a/pandas/tests/dtypes/test_dtypes.py b/pandas/tests/dtypes/test_dtypes.py
index 8df222e8fb59d..67c4fef7079e2 100644
--- a/pandas/tests/dtypes/test_dtypes.py
+++ b/pandas/tests/dtypes/test_dtypes.py
@@ -40,7 +40,12 @@ def test_equality_invalid(self, dtype):
         assert not is_dtype_equal(dtype, np.int64)
 
     def test_numpy_informed(self, dtype):
-        with pytest.raises(TypeError, match="data type not understood"):
+        # npdev 2020-02-02 changed from "data type not understood" to
+        #  "Cannot interpret 'foo' as a data type"
+        msg = "|".join(
+            ["data type not understood", "Cannot interpret '.*' as a data type"]
+        )
+        with pytest.raises(TypeError, match=msg):
             np.dtype(dtype)
 
         assert not dtype == np.str_