Season 4 Episode 12 of DC's Legends of Tomorrow is named as "The Eggplant, the Witch & the Wardrobe". The episode's title is a reference to the first Chronicles of Narnia novel The Lion, the Witch and the Wardrobe. What is the reason behind using the word eggplant in the title? Does it refer to Brinjal which is also known as Eggplant?
Ok, I'll give this a shot too, but it's also heavily language-specific context.
Like a lot of episodes, the title is a reference to something you have acknowledged. "The Lion, the Witch and the Wardrobe" The Witch part is related to Constantine's magical powers and the Wardrobe is likely a reference to the purgatory they find themselves in (like Narnia, another dimension)
For the eggplant part, I'll quote a review found here
Tied to Nate’s story is Zari’s crush. Yes, this means that the “eggplant” portion of the episode title meant exactly what you thought it did when you first read it.
Lately the eggplant emoji has taken a sexual connotation. Once again, a quote (spoilered for decency - won't ruin the show)
The eggplant emoji is a long, purple eggplant, but it’s really just used to represent a penis.
So it is a reference to the intimacy that Zari wants with Nate.