I looked up a word from a Patrick O'Brien book about two weeks ago (I forgot what exact word). It was clear from the context that it was a type of sail but I wanted to know what type of sail as the action implied it was an important type. The dictionary promptly told me that it was "a type of sail"...
Anyway, I'm not used to looking words up. I started reading books in English about 20 years ago and obviously they were paper books. I had only seven books (given to me for free) and no dictionary which I read again and again for about a year or two. To begin with I probably knew half the words in every sentence, but context saved me. When context definitely did not help I wrote the word down and asked the next native I met (well, the next acquaintance not really random strangers...).
Still, context can sometimes be misleading.
For about a year or more I thought that "bugger" is a pseudo swearword like "gosh" or "darn" because of how I heard it on TV a couple of times. Once my "internal dictionary" classified it as harmless I started using it frequently and with much gusto, to express frustration or astonishment in "polite" company where I could not swear.
And then I actually found out what it really meant!