"pertaining to expense," c. 1600, from Latin sumptuarius "relating to expenses," from sumptus "expense, cost," from sumere "to borrow, buy, spend, eat, drink, consume, employ, take, take up," contraction of *sub-emere, from sub "under" (see sub-) + emere "to take, buy" (from PIE root *em- "to take, distribute").