'Shat my dacks' is the past
tense for 'Shit my dacks'. This term is commonly
used when someone was scared shitless when looking back on
past events.
Morgz: Oi
dickhead, we're gonna go see IT Chapter 2 on Friday night. You coming?
Dale: Ahh fuck I dunno aye, last
time I watched a horror movie, I nearly shat my dacks... not a good fuckin
time.
Daryl: *laughs hysterically*
Teacher: THAT LANGUAGE DOES NOT RELATE TO THE GEOGRAPHICAL CHANGES IN BUSINESS, DALE!!!!!
*class laughs so hard they all shit their dacks*