Symbolism, Imagery, Allegory
Here's a real shocker: the titular (hee, hee) terms "tar baby" is also one of the major symbols of this novel. And here's another shocker: in a novel where morality only exists in a gray area and nothing is really what it seems, the term "tar baby" also exists in a sort of symbolic gray area, meaning multiple different things throughout the novel.
A little bit of background: the term "tar Baby" has been used to talk about bad situations that are made worse by struggling, like a being caught in quicksand or a tar pit. The original source of the term is from the traditional American story of Br'er Rabbit. In this story, a fox gets fed up with Br'er Rabbit, because of the rabbit's wily ways, and the fox devises a plan to catch the rabbit. He decides to create a small human figure out of tar. He leaves the "tar baby" in the road, and when Br'er Rabbit passes by, he greets the tar baby. Not receiving an answer, Br'er Rabbit gets fed up and tries to punch the tar baby. Br'er Rabbit's arm gets stuck, and the more he tries to struggle the more covered in tar he becomes.
For Son, Jade is "tar baby" because his lust for her traps him. Even at the end of the novel, Son is stuck in his infatuation for Jade.
Son brings up this meaning specifically when he rapes Jade, saying, "So he got this great idea about how to get him. How to, to trap… this rabbit. And do you know what he did? He made him a tar baby. He made it, you hear me? He made it!" (9.299). In other words, Son is saying that he blames Jade for seducing him in the first place, rather than taking responsibility for what he's doing.
Apart from just referring to sticky situations, the term "tar baby" has taken racist undertones, and has become racist term that refers to children from black families. It also contains the infantilizing overtones of racism: recall how black men were referred to as "boys" in the Jim Crow South. A quick internet search shows just how sticky this term has gotten for many people, including politicians.
How does the racist implication of "tar baby" play out in the novel Tar Baby? Let us count the ways! Jade is still trapped (stuck) in her role as a daughter at the very end of the novel: Ondine tells her that it's her racial ad cultural duty to be a good daughter first and foremost. Son's name is freaking "Son." He's trapped forever in the role of boyhood. Jade calls out Son on being infantile, and the question "Mama-spoiled black man, will you mature with me?" (9.287) is posed. Ondine and Sydney are stuck in servile roles in the Street household, and because they are bossed around so thoroughly they're given same (lack of) power as children. The list goes on.
And in a literal vein, Jade becomes a tar baby when she gets stuck in—you got it—a tar pit.
In a mind-blowing twist, the symbol of the tar baby becomes a tar baby. The idea of tar babies is so omnipresent and so multi-faceted that the reader becomes stuck in their effort to try to get at one single meaning of tar baby. The harder the poor reader tries to find one ultimate meaning of tar baby, the harder it is to get unstuck from all the surrounding meanings of tar baby. Ka-pow! There goes your mind.