What's the meaning of 'whereby'?
Script
The term acquisition is preferred to "learning."
Because many psycholinguists believe that no psychological theory of learning, as currently formulated, is capable of accounting for the process whereby children come to achieve a fluent control of their native language.
Question
1. What is the meaning of 'whereby' in this script?
2. The term acquisition is preferred to "learning."
-> Is it mean that "acquisition" is much more popular than "learning" in terms of usage?
Thanks for your kind help!