Jackie calls every character by their first name on That '70s Show.
Mila Kunis' Jackie Burkhart always called every character by their first names, and it wasn't just a meaningless quirk.
Since she was the youngest character among the regular cast, Jackie's obvious desire to claim superiority over others by looking dominant made her feel like the mother figure of the gang.
This, along with the fact that she dated a couple of guys in the group, showcased her habit of naming people by their first names.
It is especially obvious when Jackie uses first names, portraying her as the unique one. But it might be specifically for this purpose that Jackie brings this contrast.
As a girlfriend of Kelso's, she's not even part of the band. She's friends with them by default, and she's much younger than them. She's perceived as a privileged and spoiled girl for the most part, while she clashes with Eric the most.
Jackie's usage of first names tends to be the means by which she identifies herself. There's something distinctly maternal and polite about choosing the first name, so Jackie seeks to age herself.
Basically, Jackie behaves as a group matriarch who suits her preferences of actions, but that can't be the only explanation she prefers to ignore nicknames.
On the other hand, Donna is shown as "one of the guys" or "the girl next door," while Jackie is optimistic and self-assured, seeking recognition and admission from others as the show progresses.
Where others may find her high-maintenance, her strong sense of bounds, and evident emotional maturity are predicated on her status as a leader.
Jackie doesn't have to stick to what anyone else does, because she relishes in her unrelenting sense of self.
It is evident from her confident sense of dress and inability to forsake how she strives to climb above the crowd, and calling her mates by their first names regardless of their norm is one of the several ways in which she does this.
Additionally, there's the question of love in the series. If anyone is romantically engaged, they sometimes call their new lover a pseudonym or a moniker than the rest of their buds.
This is the symbol of love, but it provides a feeling of possession. Jackie masks her fear and segregation below the facade of irrationality and selfishness, but she seems to be yearning for affection and a feeling of belonging.
When her father is jailed, her mother leaves her, making it clear that Jackie has a troubled home life and thus looks for intimacy with the guys.
Throughout the series, she gets in a relationship with Kelso, Hyde, and Fez, naming Kelso "Michael" and Hyde "Steven," underlining her intimate friendship or ties to them.
Their pals are needed to call them by their family names, but Jackie stands out as somebody close enough to talk to them in a more unique manner.
While never shown to be an intellect, Jackie is pretty smart in her own right. Her decision to use first names could be a means by which she sets the others only a little off-the-clock, making them wonder how she perceives them.
Jackie may have been dismissive of others, and even downright rude, but the others may have felt a little bit of insecurity because they didn't use their friends' titles.
The way she influenced or changed other people was of immense interest to Jackie because there's a possibility her unusual name-giving was just an underlying way to manipulate the feelings of others.
Like a Disney villain, Jackie is aware of her potential and uses them unwaveringly, making her one of the most dynamic and interesting characters of That '70s Show.