The default analyzer for the :class:`whoosh.fields.TEXT` field does not do
-stemming or accent folding.
In order to allow
+stemming or accent folding.
The stemming filter applies the stemming function to the terms it indexes, and
-to words in user queries. So
+to words in user queries. So in theory all variations of a root word ("render",
+"rendered", "renders", "rendering", etc.) are reduced to a single term in the
+index, saving space. And all possible variations users might use in a query
+are reduced to the root, so stemming enhances "recall".
The :class:`whoosh.analysis.StemFilter` lets you add a stemming filter to an
* It increases the size of the index relative to stemming, because different
word forms are indexed separately.
* It acts like an ``Or`` search for all the variations, which is slower than
searching for a single term.