BRAIN
(verb - to hit in the head) - bash, boff, bean
(noun - body part) - head, bean, dome
(noun - cognitive sense) - mind
(noun - smart guy) - buff, whiz
A four letter word meaning not kosher is: tref
The word pine can have that meaning.
Mind.
pass
A four-letter word for cooking fat is "lard".
into
skull protects the brain
stop or halt is a four letter word meaning the opposite of go.
A four letter word meaning the foundation of something is base.
Rend is a four letter word that means to tear into pieces. Tear is also a four letter word meaning to pull apart.
A four letter word meaning to grow light as the sun rises is dawn.
Wash is a four letter word meaning "to clean with water".