Gasunlight

/gahs-un-liet/
(v) to gaslight by underexaggerating or understating.

(n) Gaslighting by underexaggerating or understating.

Person A: Didn't you only finish one problem of your math homework last night?
Person B: No, I finished all of them.
Person A: Are you sure about that? I looked in your bag and I saw that your homework was not complete.
Person B: Don't gasunlight me, I left that homework assignment at school today.
Person A: How am I gasunlighting you?

Person B: You are manipulating me by questioning my powers of reasoning by understating what I finished. I didn't just finish one problem, I finished all seven problems, ask Ms. Goofyson, she'll say the same thing.
Person A: We'll see about that. (calls teacher)