Pressure point in thumb question

Hey all, I am new to this forum and new to martial arts in general. I have a question for y'all. First, I should say where this question comes from. Not to long ago I met one of my uncle's friend (Spec. Forces) and he showed (rather put) a move on me. It involved grabbing my hand and applying pressure on the point in my thumb. It was an interesting experience to say the least. SO this brings me to my question, where is the pressure point in the thumb, and how do you apply this move? Also is there a name for this particular move? Any and all help is appreciated. Thanks!

lung #10: Located at about the midpoint of the first metacarpal, ont the thenar prominence in the lateral abductor pollicis brevis and opponens pollicis muscles.It is found in the "meat of the thumb" on the borderline between the (reddish) skin of the palm and the skin of the back of the hand.

Press with the fingertips against the bone of the thumb.Use this point when squeezing the thumb towards the little finger in tuite techniqeus.

I hope this is what you were looking for.