Half-price means costing only half the usual amount. Sold half-price.
The usual amount is whatever the shop says it was, which is why the rules on it are strict. A half-price offer must be against a price genuinely charged for a real period.
1adjectivehalf-priceCosting only half the usual amount.
“Everything was half-price on the last day and still did not sell.”
half-price is a quality.
Middle English
half
English
half
English, today
half-price
From half- + price. half comes from Middle English half. From Middle English half, halfe from Old English healf (“half”); as a noun, 'half', 'side', 'part', from Proto-West Germanic halb, from Proto-Germanic halbaz. 2
Etymology from Wiktionary, CC BY-SA