<s>
An	O
online	O
dictionary	B-Operating_System
is	O
a	O
dictionary	B-Operating_System
that	O
is	O
accessible	O
via	O
the	O
Internet	O
through	O
a	O
web	B-Application
browser	I-Application
.	O
</s>
<s>
Many	O
dictionaries	B-Operating_System
have	O
been	O
digitized	O
from	O
their	O
print	O
versions	O
and	O
are	O
available	O
at	O
online	O
libraries	O
.	O
</s>
<s>
Some	O
online	B-Application
dictionaries	I-Application
are	O
organized	O
as	O
lists	O
of	O
words	O
,	O
similar	O
to	O
a	O
glossary	O
,	O
while	O
others	O
offer	O
search	O
features	O
,	O
reverse	B-Data_Structure
lookups	I-Data_Structure
,	O
and	O
additional	O
language	O
tools	O
and	O
content	O
such	O
as	O
verb	O
conjugations	O
,	O
grammar	O
references	O
,	O
and	O
discussion	O
forums	O
.	O
</s>
<s>
The	O
variety	O
of	O
online	B-Application
dictionaries	I-Application
for	O
specialized	O
topics	O
is	O
enormous	O
,	O
covering	O
a	O
wide	O
range	O
of	O
fields	O
such	O
as	O
computing	O
,	O
business	O
and	O
investing	O
,	O
along	O
with	O
almost	O
any	O
other	O
class	O
of	O
trade	O
,	O
science	O
,	O
art	O
,	O
or	O
common	O
interest	O
with	O
its	O
own	O
terminology	O
.	O
</s>
<s>
The	O
following	O
is	O
a	O
concise	O
list	O
of	O
online	O
English	O
dictionaries	B-Operating_System
whose	O
definitions	O
are	O
based	O
upon	O
well-established	O
content	O
.	O
</s>
<s>
American	O
Heritage	O
Dictionary	B-Operating_System
American	O
Heritage	O
Dictionary	B-Operating_System
of	O
the	O
English	O
Language	O
,	O
Fifth	O
Ed	O
.	O
</s>
