Format a dictionary for print publishing? (An actual dictionary book, not an InDesign dictionary)

I've ridden along on a few dictionary projects, and my immediate first question is "Have you talked to your scholars?" Are you sure they're not using some kind of lexicography tool already? Because, if so, the workflow I'd suggest would be to work with the XML output from, say, FieldWorks - a tool expressly built with dictionary production in mind! -  which can then be massaged into a format that is easy for your layout tool to ingest. If you do wind up using InDesign, and your lexicographers store their data in literally almost any kind of database at all, it's worth looking at using that DB to produce InDesign Tagged Text, which has some ease-of-use advantages over either XML or CSV.  

Like most of the posters here, I think that Frame has a few layout tools that make for much easier dictionary creation. If Frame isn't an option, I'd also consider XeTex. But given what you've told us thus far, I think that your choice of layout tool is one of your less weighty workflow decisions. 

@Anshuman37504615cr3p

The idea to use Excel is a great one. You can also use Google Sheets to work as a team.

Then, you have two options:

1) import - or copy&paste - data as a table to InDesign - apply ParaStyles to columns - convert table to text,

2) use Excel to create InDesign Tagged Text - it's rather more complicated so you would need extra help. 

Others mention CharStyles - you would've to show use an example of the raw data and how it should look like in the end - so we can determine how to apply them - directly or through Nested or GREP Styles.

I think Eugene is right, this can probably be done without data merge but as he says paragraph and character styles will be absolutely essential.

If the information is strictly structured in the Excel files getting it into InDesign is not difficult and you can certainly get advice on that here.

Depending on what the "foreign" language is you may have to put some effort into ensuring character sets, accents and diacriticals are correct. Will the Excel file contain phonetic symbols? If so you will need to be sure they are preserved and you have a suitable font in InDesign. I hope that's not teaching granny to suck eggs!

Depending on the size of the dictionary, you may also want to use InDesign books to split the work into smaller parcels. How many entries do you expect to have?

Perhaps the most important factor will be whether you have full and final content in the Excel file(s). If you have to allow for rounds of proofing and making corrections then you need to establish a workflow for that from the start.

(I'm sure Willi's comment that this would be a good project for FrameMaker is correct — I have only very second-hand knowledge of FM — but there are good reasons to do this in InDesign. For instance if you need freelance help you are much more likely to be able find people who can use InDesign. Also InDesign is cross-platform, if that matters to you.)

You should consider to do it in Adobe FrameMaker instead of InDesign. FrameMaker has some critical properties in paragraph styles which does not offer as Inline Paragraphs. I would not do it in InDesign.

Not sure Data Merge would be the best approach.

Have you tried a sample set of about 10 words and definitions?
I'd just insert the Excel file as a Text file instead then apply styles.

Paragraph styles and Character Styles would be a must. 

You can setup GREP styles, and Nested Styles inside the Paragraph Style

This would apply Character Styles automatically to format the dictionary set automatically.

There's some fantastic videos here on GREP 
https://www.theindesigner.com/blog/category/grep

Also search the list on the left for Nested Styles

There's also great videos on Data Merge - but I don't think it's appropriate for this project.
Maybe it is - it's just not the way I would do it.