Related Clues:

• One side of a store sign
• Open partner
• Word with in, out or up
• Discount letters
• Like some disc. items
• Type of vb.
• Closed tight
• Flawed, as mdse.
• Not open
• Opposite of 18-Across
• Isolated, with "off"
• Marked down, most likely: Abbr.
• Sale item, maybe: Abbr.
• Shuttered
• Like the verb 'to be': Abbr.