This is the 4522nd most frequent Swedish word.
vänlig
Friendly; kind.
In this sentence, the word 'vänlig' is used in the expression 'Var vänlig och...', which is a polite way to request someone to do something, similar to 'please' in English.
Var vänlig och stäng dörren.
Please be kind and close the door.
Here, 'vänlig' describes the person's attitude, implying that he is being nice and considerate towards others in his behavior.
Han är alltid vänlig mot sina kollegor.
He is always kind to his colleagues.
In this case, 'vänlig' is used to characterize the smile as being warm and friendly, indicating affection.