is the pleasant, even sweet, smell that lingers in the air after an action is over...
When you go to a restaurant to eat, often you will not remember what you ate, but how you felt...are you carrying away a bouquet of a totally good experience or is the lingering smell one that you would not want to experience again...
When you meet someone you will not remember what she/he wore, often you won't even remember their features, and you will certainly not remember the mundane, usual criteria of where they live/work/status in society (a figment of people's imagination anyway)....but something about them stays with you...if you've clicked, the fragrance is a pleasant one, and if the meeting has in any way been abrasive, then that is the odor that lingers...
When you visit a place, for instance the hills, maybe you won't be able to retain the picture in your mind, but how you felt in the presence of the magnificence of nature will surely remain with you, ever after offering solace and comfort and a beautiful feeling...
When you do something you really like to do...it could be anything....that warm feeling lingers long, long afterwards...the fragrance stays with you....
So then what kind of fragrance should you leave.....be pleasant, polite, and interested in everyone and everything for everyone and everything crosses your path for a reason....
(if the interaction with and about the everyone and everything is good, it will leave a fragrance in your heart, and if it isn't, then you can learn your lesson and move on...)