opiate. 1  a drug containing opium or its derivatives, used in medicine for inducing sleep and relieving pain. 2  any sedative, soporific, or narcotic. 3  anything that causes dullness or inaction or that soothes the feelings. 4  mixed or prepared with opium. 5  inducing sleep; soporific; narcotic. 6  causing dullness or inaction. 7  to subject to an opiate; stupefy.
Each puzzle has one and only one unique solution, and each can be solved using only pure logical deduction-guessing and trial-and-error methods are never required for these puzzles. If you're new to numbergrids, try the smaller puzzles first, then move on to the larger ones.
Diagonal Sudoku. Each puzzle consists of a 9x9 grid containing given clues in various places. The object is to fill all empty squares so that the numbers 1 to 9 appear exactly once in each row, column, diagonal and 3x3 box.