Underestimate 

1. Rate something lower than its real/actual value , under appreciate.
2.Estimate/ rate someone lower than his/her actual potential, qualifications.

You underestimated that problem because you are not familiar with it.
Don't underestimate 'em simply because they are young.

Julian: Ask your lil bro to quit that chalenge it is very hard for him.
John: Don't underestimate my little brother his able.

Underestimate by julianmosha January 2, 2017

Underestimate 

Thinking something would be easier to do until you start to do it, what some people would call doing something from an armchair.

Don't underestimate the funny/silly looking guy/girl trying to disarm you, for he/she can go from funny/silly to serious and grown looking/sounding like a light switch, and bad things happen to people that underestimate him/her. His/her bag of tricks is deep, and they can all die.

Underestimate by The Original Agahnim August 25, 2021

You underestimate my power

The act of declaring that one is good at something right before fucking it up.

Derives from Star Wars Episode III: Revenge of the Sith where Anakin Skywalker says this to his former master Obi-Wan Kenobi right before lunging at him and getting his left arm and both of his legs cut of by a lightsaber.

Obi-Wan: "It's over Anakin, I have the high ground"
Anakin: You underestimate my power!"
Also Anakin: (Lunges at him and gets fucked by his laser sword and then caught on fire)

You underestimate my power by buttonmasher525 January 2, 2018

Underasstimate

When you think your ass will fit in to something i.e. pants or a small space.

I wanted to get these new skinny jeans, but I Underasstimated and had to get them several sizes up.

Underasstimate by Gingerella August 20, 2012

unneresticate 

to purposefully avoid teaching someone about sex

she unneresticated her son

unneresticate by forrest queen November 10, 2013

under-estimate

an estimation that is too low; an estimate that is less than the true or actual value

I think Kendall under-estimated allen when they went out to the movies.

under-estimate by AKB jr January 28, 2008

underestimated 

best NA clan for c-ops

underestimated rapes 6s in tournaments

underestimated by AmbitiousVSNY April 1, 2021