What is a lexicographic order? Here are some definitions.
Noun
(mathematics) Formally, given two partially ordered sets A and B, the order ≤ on the Cartesian product A × B such that (a,b) ≤ (a′,b′) if and only if a < a′ or (a = a′ and b ≤ b′).
(mathematics) Given sets (A1, A2,..., An) and their total orderings (<1, <2,..., <n), the order <d of A1 × A2 ×... × An such that (a1, a2,..., an) <d (b1,b2,..., bn) iff (∃m > 0) (∀ i < m) (ai = bi ) and (am <m bm )
