Is it dishonest to omit publications in one's CV?
Since there are no rules on how a CV should look like it will be hard to find references. There are also different preferences from different people, so you cannot avoid "opinion based" answers here.

In my opinion it doesn't look good if you just leave out a publication and make it look like those are all of your publications.
However, it is very unusual to include all publications in a CV once the number gets bigger. How many to include is up to you, most of the time I've seen around 10. To make clear that those aren't all of your publication there's usually the phrase "selected publications" and in that case you want to include the "best" or most relevant publications or a very representative sample of the things you did. So the important part is to actually tell the reader that it is only a part of the full publication record, but if you do so it is definitely no problem.

The guidelines from columbia university say:


  Publications - These can also be listed on a separate page, or you may include a distinct section called “Selected Publications.”


This is also true for awards, fellowships and things like that. Once the list get's very long you might only list the most prestigious ones.