Like everyone, I have at least 3 vocabularies.
Those I speak, write and read in increasing order of size.
Mine developed largely through wide reading, and talking with articulate people; however, a major contribution was the exercise I was made to do as a 5th and 6th grade student in the American School in Manila in the Philippines.
You had to identify 20 words from a dictionary; learn how to spell them and then use them in context in a sentence. Naturally I had abundant fun, explaining that American English spellings of things like “color” and “behavior” were wrong. Learning words like peremptory, just so you could say to your teacher, “Ma’am, you are speaking to me in a peremptory fashion. Why?” was excellent fun.
I learned to love words, and still do.
My last enjoyment was telling a Coastguard colleague things were “copacetic”.
If someone uses a word you don’t understand, ask them. They may not know the meaning either! If they do, learn it – then pay it forward 🙂
Be proud of your vocabularies; you learned them.