1 words in general: This book contains some difficult vocabulary.
az: lüğət, dil
ru: лексика
2 (the stock of) words known and used eg by one person, or within a particular trade or profession: He has a vocabulary of about 20,000 words; the specialized vocabulary of nuclear physics.
az: söz ehtiyatı
ru: словарный запас, словник
3 a list of words in alphabetical order with meanings eg added as a supplement to a book dealing with a particular subject: This edition of Shakespeare’s plays has a good vocabulary at the back.
az: lüğət, sözlük
ru: словарь, словник