• Menu icon > Options' > 'Composition' > 'Spelling' tab

Update....a MAC will locate same info under 'Thunderbird' > 'Preferences' Select which language to use.

Select checkbox 'enable spell check as you type'. click on 'Ok

In new 'Write' window, mispelt words will be underlined. Click on 'Spelling' to open the Check Spelling window.

Thanks for the reply. I am interested in finding the definition of words I don't understand, not how to correct spelling.

In a previous (way back) version I could right-click on a word and I could select dictionary to define the word; I cannot do that here.

Highlight word and right click on it. I have the option in list to 'Search google for 'word

There used to be an addon that did this, but it may not work under current versions. There has notbeen any update for some time. https://addons.thunderbird.net/en-us/thunderbird/addon/wordreference-translator/

Thanks for the input. Your option is not supported in my version of TB. I do get an option to search Bing for the definition, I'll use that.

Thanks.

re :I do get an option to search Bing

Perhaps this is because you have set up 'Bing' as the default search. 'Thunderbird' > 'Preferences' > 'General' Default search engine.

Thanks, you are correct. I can live with this but am still puzzled as to why the dictionary I downloaded is not available to me.

re :puzzled as to why the dictionary I downloaded is not available to me

I presume it is suitable for use on your current version of Thunderbird.

In 'Addons' > Dictionaries Q: Is the dictionary listed and enabled ?

Q: Have you restarted Thunderbird after installing the dictionary ?

Q: Have you selected that dictionary in : 'Thunderbird' > 'Preferences' > 'Composition' > 'Spelling' tab  ?

Under add-ons, "This add-on provides the Mozilla-maintained Hunspell US English dictionary that is shipped with Thunderbird 60" --- I have TB 60.4.0

The dictionary IS listed under add-ons and is Enabled.

I restarted TB multiple times after i installed the dictionary multiple times.

The dictionary IS selected.

What am I supposed to see upon highlighting a word and right-clicking.?

re :What am I supposed to see upon highlighting a word and right-clicking.?

If you have set Thunderbird up to highlight mispelt words as you type in a new 'Write' message window - as previously mentioned, then they will get a red underline as you type. You then click on 'Spelling' to open the 'Check spelling' window to work through anything underlined. Or highlight a word and click on 'Spelling' to edit that particular word.

Right click offers nothing in checking spelling if you are reading received emails. Dictionaries are used when composing emails.

If you are in a new Write window composing an email, the right click on highlighted word will offer eg: 'Spelling suggestions' or 'Add to dictionary' etc Adding words to 'Personal dictionary' does not effect any installed dictionaries.

I would like to use dictionary IN A MESSAGE I RECEIVED to look up a word I am not familiar with. I don't have a problem with spellcheck.

re :but am still puzzled as to why the dictionary I downloaded is not available to me.

It is available. Dictionaries in Thunderbird are used when composing an email. They are used in the 'Spell Check'. They offer potential spellings for incorrectly spelt words. They do not offer 'definitions'. It is assumed that you know what you are talking about, but may have incorrectly spelt the word due to a typo error.

re :I would like to use dictionary IN A MESSAGE I RECEIVED to look up a word I am not familiar with.

The addon dictionaries are not used for general seach for meanings/definitions of unknown words. If you need definition then.... Highlight word and right click on it. Select 'Search Bing for 'word'.

In the past there were a couple of types of dictionary addons offering a definition style but they are no longer up to date - not maintained by their authors and therefore do not work with recent versions of Thunderbird.

Thanks. Of course I know the meaning of the words I use when writing a message.