The phrase "limited vocabulary" means that someone has a small number of words they use or understand when speaking, writing, or communicating. Full definition
This approach is feasible for combining two small speech models, such as with the test samples of two people using a very limited vocabulary. (scientificamerican.com)
The concept of creativity was a concern in this study as results showed that students, teachers, and arts professionals exhibited poor knowledge and limited vocabulary in order to articulate learning through creativity. (artsedsearch.org)
Whatever the cause, an initially limited vocabulary might be necessary for the emergence of an expressive language. (discovermagazine.com)