The choice of dictionary is bound to a particular language and country code. For
example "en" and "GB". One can define multiple dictionaries for "en" and "GB"
but they are all checked for spelling and it is not possible to select which one
should be used. It would be extremely useful to do so.

For example, in the UK there are two distinctly different "house styles": one
based on the OED house style and the other based on colloquial English usage.
Sometimes one needs to use one and sometimes the other. We have created two
different en-GB dictionaries conforming to the two house styles, but there is no
way to select which one should be used without manually editing the
dictionary.lst file and restarting OOo. 

It is understood that the same issue arises with other languages too, such as
German.

This is a request to decouple the choice of dictionary to use from the choice of
language and country: e.g. "en" and "GB", thereby allowing multiple dictionaries
for one language/country, and to provide the user with the capability to select
 which dictionary should be used without having to restart OOo. Thus if one
selected "en" and "GB", one would have a further choice whether to use the
"English (UK)" or "English (OED)" dictionary. (Assuming both are installed.)

An alternative solution would be to define additional language variants, such
as, for English, the language "English (OED)" and allocate it a different
designator such as "en" and "OED" (rather than using "en" and "GB"). en-OED
would be non-country-specific flavour of English. Whilst less ideal than the
request above this solution may fit better with the current architecture of the
application.