To feel tired and dissapointed. You feel like giving up something you put in alot of effort. ท้อแท้ is the full version.

thanks

1) ท้อ​ as a verb : discouraged, be downhearten. It's the feeling when you failed doing things or didn't accomplish things you put a lot of effort in as much as you wanted. 2) ท้อ​ as a noun : a peach Yeah!!! It's a fruit.... :) Thai call it "ลูกท้อ" in full.