Is Shit Equals To Pass Motion?

I was on my way to work today when I thought of something funny.

I recalled when I was younger, my mum used to tell me :

"Tell the teacher immediately IF you want to pass motion".

What sort of word is pass motion anyway?! I got an inkling that perhaps it is a word from Brit-english, but upon googling it out ... hell no!

(source)

Forums insisted that "pass motion" is actually a Singlish word from the Malay slang of buang air besar (literal translation is throw water big. Very puzzling isn't it?)

I think those forums are confused! Pass Motion definitely does not equals to throw big water.

(and whenever I think of 'pass motion' , a picture of a river comes to my mind, I don't know why but yeah it did)

I thought and I thought, and I concluded that maybe she (my mother) was just being cautious not to use vulgarities (ie SHIT) as I was only 6 years old at that time.

Does your mother use the word 'pass motion' too?

Ah, the wonders of the english language.....

P/s Some actually thought that pass motion is a term for scientific theory! Omg. Who are you kidding man??!