You may also have to clear your browser cache as well. You should be able to make changes in  admin / settings / languages. You just need to search by the keywords you are wanting to change.
Also I'm thinking that database changes won't show until cron runs. I may be wrong, but I have seen some of those type changes take a little longer.

Thanks for the response...

So checked the info in the settings/language page and the updates are correctly displayed.

manually ran the cron job but page remains unchanged...

accessed page via private browser session but still unchanged...

#confused...

Thanks

JB

Kinda sounds like something added to a theme. I don't see that particular language in the base theme.
You said in the first post that you changed dev mode, and ran the cache cleaner plugin. Just making sure. The Cache Cleaner plugin says to use it when dev mode is not set to true. Not sure what it will do if you do that. When you set dev mode to true just go back to your site, and refresh the page. Then set it back to false. The cache cleaner plugin works well, but I don't think it does some of the things the other method does.
If it is something specific to your theme, you may need to contact the theme dev.