STUMPERS LXV
Credit: GAMES Magazine - Feb. 1999
Darren Rigby  (adapted)

Think of an eight-letter word that has no repeated letters. Each word on the left in the pairs below can be spelled entirely with letters of that word, but each word on the right cannot. For example, if the original word were SAMPLING, then one such pair might be PLAN - SMUG.  SAMPLING contains all the letters in PLAN, but lacks the U in SMUG. In the pairs below, all eight letters of the governing word are used. What's the word?

BILE - SOUP
PIER - BOIL
CURB - SLIP
RICE - PUCK
PURE - LUCK

HINT:
#1: Notice that there are two letters on the left that do not appear on the right.
#2: These are the first two letters of the answer word.

Answer:

The word is REPUBLIC.