<s>
In	O
metadata	O
,	O
a	O
synonym	B-General_Concept
ring	I-General_Concept
or	O
synset	B-General_Concept
,	O
is	O
a	O
group	O
of	O
data	O
elements	O
that	O
are	O
considered	O
semantically	O
equivalent	O
for	O
the	O
purposes	O
of	O
information	O
retrieval	O
.	O
</s>
<s>
Although	O
a	O
group	O
of	O
terms	O
can	O
be	O
considered	O
equivalent	O
,	O
metadata	O
registries	O
store	O
the	O
synonyms	B-Application
at	O
a	O
central	O
location	O
called	O
the	O
preferred	B-General_Concept
data	I-General_Concept
element	I-General_Concept
.	O
</s>
<s>
According	O
to	O
WordNet	B-General_Concept
,	O
a	O
synset	B-General_Concept
or	O
synonym	B-General_Concept
set	I-General_Concept
is	O
defined	O
as	O
a	O
set	O
of	O
one	O
or	O
more	O
synonyms	B-Application
that	O
are	O
interchangeable	O
in	O
some	O
context	O
without	O
changing	O
the	O
truth	O
value	O
of	O
the	O
proposition	O
in	O
which	O
they	O
are	O
embedded	O
.	O
</s>
<s>
The	O
following	O
are	O
considered	O
semantically	O
equivalent	O
and	O
form	O
a	O
synonym	B-General_Concept
ring	I-General_Concept
:	O
</s>
<s>
A	O
synonym	B-General_Concept
ring	I-General_Concept
can	O
be	O
expressed	O
by	O
a	O
series	O
of	O
statements	O
in	O
the	O
Web	B-Language
Ontology	I-Language
Language	I-Language
(	O
OWL	B-Language
)	O
using	O
the	O
classEquivalence	O
or	O
the	O
propertyEquivalence	O
or	O
instance	O
equivalence	O
statement	O
–	O
the	O
sameAs	O
property	O
.	O
</s>
