By default, means without any alteration -do normal functions .
defaulter --may be bankrupt--diwaliya.

In the computer world, the word default means, what your computer will do when you don't tell it to do something else. When you type a document on your computer, the font selected is probably Times New Roman, Arial, Helvetica or Garamond. The font that your computer has set every time you go into the program is the default font.