An acquaintance that you invite to important functions such as weddings and baby showers, but wouldn't normally hang out with otherwise. Like a carnation is a filler flower in a bouquet, the filler friend gives out the illusion that you have more friends than you actually do.
Since my fiance invited all of his hockey team to our wedding, I sent out an invitation to all of my filler friends so that I won't look like a loser with no friends at my wedding.
A friend who is used as a filler in social situations.
1. Having a party and inviting your filler friends just so there are more people, to make the party look more full.
2. Inviting a filler friend to a movie because you don't want to go alone.
"Hey I got an extra hockey ticket, ya wanna go with me?"
When someone that you barely know has no one they usually hangout with at a social event of some sort, and start acting like your friend.
I'm so tired of being a filler friend >.>