from
WordNet (r) 3.0 (2006)
stemmer
n 1: a worker who strips the stems from moistened tobacco leaves
and binds the leaves together into books [syn: {stripper},
{stemmer}, {sprigger}]
2: a worker who makes or applies stems for artificial flowers
3: an algorithm for removing inflectional and derivational
endings in order to reduce word forms to a common stem [syn:
{stemmer}, {stemming algorithm}]
4: a miner's tamping bar for ramming packing in over a blasting
charge
5: a device for removing stems from fruit (as from grapes or
apples)
from
The Free On-line Dictionary of Computing (8 July 2008)
stemmer
stemming
<information science, human language> A program or {algorithm}
which determines the morphological root of a given inflected
(or, sometimes, derived) word form -- generally a written word
form.
A stemmer for English, for example, should identify the
{string} "cats" (and possibly "catlike", "catty" etc.) as
based on the root "cat", and "stemmer", "stemming", "stemmed"
as based on "stem".
English stemmers are fairly {trivial} (with only occasional
problems, such as "dries" being the third-person singular
present form of the verb "dry", "axes" being the plural of
"ax" as well as "axis"); but stemmers become harder to design
as the morphology, orthography, and {character encoding} of
the target language becomes more complex. For example, an
Italian stemmer is more complex than an English one (because
of more possible verb inflections), a Russian one is more
complex (more possible noun declensions), a Hebrew one is even
more complex (a {hairy} writing system), and so on.
Stemmers are common elements in {query} systems, since a user
who runs a query on "daffodils" probably cares about documents
that contain the word "daffodil" (without the s).
({This dictionary} has a rudimentary stemmer which currently
(April 1997) handles only conversion of plurals to singulars).
(1997-04-09)