: characteristic of, relating to, or suggestive of a wonk: such as
a
: preoccupied with arcane details or procedures in a specialized field
She can get wonky about the economy when she wants to, but what sets her apart is her ability to tell a coherent, populist story about it in a way that other members of her party are either unwilling or unable to do. Rebecca Traister
probably alteration of English dialect wankle, from Middle English wankel, from Old English wancol; akin to Old High German wankōn to totter — more at wench