Clarify meaning of highest resolution in docstrings

Co-authored-by: Chahan M. Kropf <[email protected]>

Author: luseverin

climada/engine/impact_calc.py

@@ -92,8 +92,9 @@ def impact(
             Default: True
         assign_centroids : bool, optional
             indicates whether centroids are assigned to the self.exposures object.
-            The default centroids assignement uses euclidean distance and a threshold equal to
-            twice the highest resolution of the centroids (assuming a regular grid).
+            The default centroids assignment uses Euclidean distance and a threshold equal to
+            twice the highest resolution (smallest distance between any two nearest neighbours)
+            of the centroids (assuming a regular grid).
             Recommendation: assign the centroids directly with control
             over the distance metric and the distance threshold using
             `exposure.assign_centroids(hazard)`. In this case, set assign_centroids to ``False``.