This is the 8998th most frequent Russian word.
резкое
"Резкое" means "sharp" or "abrupt."
In this example, 'резкое' describes 'движение' (movement), indicating that it was sudden or unexpected.
Резкое движение напугало ребенка.
The sudden movement frightened the child.
In this sentence, 'резкое' modifies 'изменение' (change) and describes it as being abrupt or significant.
Резкое изменение погоды застало нас врасплох.
The sharp change in weather caught us by surprise.
Here, 'резкое' qualifies 'слова' (words), denoting that they were blunt or unkind in nature.