When we say "apply the mind", we generally mean to use our mental abilities to think deeply or to solve a problem. There are several synonyms for this phrase which can be used to express the same idea. Some of these include "engage the intellect", "utilize cognitive skills", "exercise mental capacity", "employ critical thinking", "put the brain to work", "employ the grey matter". All these phrases imply using the brain in an active and constructive manner. By using such synonyms, we can enrich our language and convey our thoughts more effectively. It is always important to take time to think and apply our minds, whether it is for our personal growth or to solve problems in our professional lives.