When studying and reading a novel in a foreign language - when/how often should one look up new words?

I think it depends on the reader. For me it’s important to look up every word I’m unfamiliar with – but then, I’m not spoken-word fluent by any means, I can only just read and translate most things in the two languages I know a bit of into English given a dictionary, paper and pencil, and enough time. I never got to a point where I could possibly read without also doing a written translation, so it never broke my concentration to look stuff up. I bet you work with more advanced language students than me, but I dont think it would disturb me too much to look up words. I do something similar when I read translated philosophy texts that have oodles of language-related footnotes, like this, and though it can lead my mind off on a tangent sometimes, I find that more often it helps overall comprehension of the sentence.

I have not tried this but when text is highly technical if the book is mine I will underline the word try to figure it out contextually and come back and look up later. If it is not mine I have a notebook to jot it down. If it is on my nook I have to look it up right away or I won’t be able to find it again.

I would always try to figure out the word from its context, then check against the dictionary. It was good form to do this every single time, and to keep notes, but if it was a good story (Verne in Italian is, in some ways, better) I’d leave it for the next read-through if I could help it.

I think it depends at which stage of learning you are at. At earlier/intermediate stages I want to be immersed in the language more and let my mind absorb it through osmosis, so if I get what it’s talking about, I move on. I like the idea of jotting down words and then coming back to them though. Another I like to do is to jot down phrases that I particularly like to try and use later.

However, once I gain a general competence in a language, and want to really refine my understanding of it, I might look things up to try to get the nuance.Thought I have to say, when it comes to nuance, people are a much better resource than dictionaries.

Whatever works for you and depending on what your goals are. If you are reading mainly to learn new words, then you should look up every word. If you are reading for pleasure, then getting the gist may be just fine.

I have a hybrid approach.
For general reading:
When I flat out don’t see how the word works in the structure, then my concentration is already blown. I then look up to word.
When I get the general understanding of how it fits and the flow is only delayed because the word is unfamiliar, I will note the word and look it up another time.
For Technical research I will look up each and every unknown. I simply can’t assume when I am doing research.

If you look up every word you don’t know, how likely is it that you will remember it? We need to be exposed to a word more than once in order to remember it. Time spent looking up lots of words is time that could be better spent reading. I would say, if you think you understand the general idea, skip the word and move on. If you see the word again, you can try and guess what it means.

I’m teaching myself German and find it quite helpful to read books and stories in the language spoken. When I come across a word I don’t understand, I like to look it up immediately, then re-read the sentence or paragraph containing it. Like asking myself “Okay, what did that really say?”

It depends on why I am reading the work. If I am reading it for the content or to improve or maintain my ability in the language, I will look up words fairly often. If I am reading it for entertainment or just to pass the time, I will look them up less often. Sometimes I will jot down words in a list and look up several at once so that I don’t break up the flow of my reading, or sometimes I will only look up a word if it appears more than once or appears in a crucial place.

A subjective sense of “getting the gist” does not entail good comprehension, so I will look up words often if comprehension is important to me. If it is a literary work, I may re-read it in translation to see what I’ve missed, which can be humbling.

Most of the time I kept reading, while writing down the unknown on a sheet of paper which only takes 2 seconds or so. Only exception: couldn’t grasp the meaning of the sentence or paragraph.

I think as often as they come across them. They should make a list of their meaning and usage.

I’d look up nearly everything I didn’t know as I came to it; or, better, skim ahead and look up as many new words as I could spot in the coming paragraphs so I could then read them fluently.

That didn’t avert the necessity of checking again when a word didn’t make sense in context and so I had to see if it was being used in a different sense or was part of an idiomatic expression.

I did try to guess at some terms on the basis of context clues, but sometimes that led to ludicrous misinterpretations.