1) Meaning/Oral vocabulary refers to words language learners use in order to understand what they hear in speech, and words they use when they speak. This involves both receptive and productive vocabulary. For listening, if they lack meaning/oral vocabulary knowledge, they would have difficulties in what they are hearing in authentic situations or from authentic texts.
2) Literate/Written vocabulary refers to words language learners use in order to understand what they read, and words they use in writing. This, again, includes both receptive and productive vocabulary. Receptive vocabulary involves being able to recognise it when it is seen. When one reads, he or she needs a number of vocabulary items to understand texts he or she is reading. Likewise, when one writes, he or she needs a number of vocabulary items to produce his or her ideas in the writing texts.
3) Receptive vocabulary concerns words language learners use in order to understand what they hear in speech, and words used to understand what they read. It is generally acknowledged that language learners need receptive vocabulary for their listening and reading. The better one’s vocabulary knowledge, the easier one would find it to understand the conversation or a large amount of reading.