In the beginning of learning Japanese you start from a Japanese to English dictionary or whatever your native language is. All is well you can understand what is meant to be understood. It serves its purpose it's doing what it needs to do until. You reach a road block and realize that the translation on the Japanese to English dictionary does not explain the definition to it's purity. That and sometimes it's not very clear on the definition at all. I see Japanese to English dictionaries as the training wheels to get into the language.
You rely on it until you can take off the training wheels and finally ride the bike with centered balance. The reason why the change has to come like a graduation day is because. You really start to realize you can't explain the definition of the word term or idiom for that matter like how a Japanese person would understand it.
I remember when I finally reached the point where the Japanese to English dictionary also didn't have a word that I was searching for in it's database. There are words that can't actually be explained in English. A website that I love using called jisho.org has been a huge help in my Japanese learning journey. I'm very grateful for this site to exist actually.
But I realized that the site had limits. There are some Kanji that are unrecognizable on the search. Because it was not in the database yet. I had to venture into another dictionary where I finally started to understand. The way the Japanese people would describe words. There's a point to this, you maybe be able to describe the meaning to someone who is learning Japanese through the Japanese to English dictionary. But to a Japanese person who does not know English and explaining the definition or concept and meaning to them how a Japanese person would describe it. You start to see that it's a challenge in itself, most likely it won't sound natural coming out of you. A Japanese person who is studying English and is at a good enough level won't mind. Because they are a language learner just like you. But to a Japanese person who is monolingual. Automatically they will sense that the explanation is off. I recommend this site https://www.weblio.jp when you finally make the jump into using a Japanese only dictionary. It's super useful, the way I slowly moved to using a Japanese only dictionary was very simple really.
It's just the matter of getting used to it. I still use jisho.org but now I make sure to only make monolingual flashcards in brainscape.com I've completely stopped making Japanese to English flashcards. Now I just make Japanese only cards. Which makes sense because now you're learning as things are intended within the target language. Not needing to translate words in your head is definitely a plus. Another thing that I started to realize is a sense of simplicity from other words that are no longer in use and what is most likely to be used in mainstream.
This is a big milestone and if you've reached this level I applaud you. Being able to learn in a foreign language is amazing accomplishment!