If you're interested in bilingual dictionaries with additional linguistic insight then I've always found wordreference.com very good: as well as the translations, most words have forum entries where people discuss the finer points of how the words and any associated expressions are used. It's not too bad for straight English either - though I tend to just log onto oed.com via my university for that.

Thanks, Mercedes.

I would suggest thefreedicitionary.com. It collects information from several dictionaries and it is the most compehensive in terms of field of knowledge. 

Thank you, Gabriela. I wasn't aware of this one. It looks great. I just added a link to my web browser.

Te agredezco mucho la sugerencia, Ana Isabel.

I send my best wishes for a happy and fruitful new year to all who have contributed to this thread.

David

The oxford online Dictionary is the best, both in it's electronic version and physical format. It gives both the English and American English definitions as well as example sentences.

Thank you for your input, Mary. I was initially put off when I saw that a paid subscription is required to access the Oxford English Dictionary (OED) online, so I've been using the Merriam Webster online dictionary (https://www.merriam-webster.com/), which is the designated source when writing or editing in APA style. This probably makes more sense on the west side of the Atlantic Ocean than on the east, considering the diverse dialects of the English Language. Inspired by your post, I went back and looked at the web site of the Oxford English Dictionary (https://www.oed.com/) and I saw that I still can't get in without a paid subscription. I continued to search for an open edition and found a library support page (https://askus.library.wwu.edu/faq/190729) with a reference to another site (https://en.oxforddictionaries.com) but when using this URL I was taken to yet another site (https://www.lexico.com/) called Lexico which has the phrase "Powered by Oxford" in its logo. It's all a bit confusing, but the upside is that this is an open access dictionary that at first glance looks like it's put together with care. Just for the sake of precision, is the version you are recommending the paid electronic version of the Oxford English Dictionary (https://www.oed.com/)?

I found a web page that explains the changes in links mentioned in my last post, revealing that Lexico is indeed an official and open-access spinoff of the OED: https://languages.oup.com/why-has-oxford-dictionaries-changed/ Thanks again, Mary, for motivating me to take another look at the OED site. There have been a lot of changes since I posted this question over six years ago.

I prefer to use Mirriam Webster and Cambridge inline dictionaries. I like their layout and explanations.

Here is the link to the Cambridge dictionary:

https://dictionary.cambridge.org/

Dear David Charles Wright-Carr

Thank you for the valuable information. For me, I'm still using a simple dictionary

https://translate.google.com/?hl=en&ui=tob

Miriam webster

How about Longman? https://www.ldoceonline.com/

David Charles Wright-Carr

Language Toolbox could be interesting!

http://itools.com/language