This is the 13485th most frequent Russian word.
напугал
"Напугал" means "scared" or "frightened."
The word 'напугал' here indicates that he caused fear or startled someone by his action, which is denoted by 'своим громким криком' (his loud scream).
Он напугал меня своим громким криком.
He scared me with his loud scream.
'Напугала' refers to the action of scaring the cat, likely unintentional and due to the loud noise of the slamming door.
Она напугала кошку, внезапно хлопнув дверью.
She scared the cat by suddenly slamming the door.
In this context, 'напугал' describes the fear caused by someone's unnoticeable approach, making others startled or uneasy.