Related Clues:

• Find a sum
• Interpose
• Supplement (with ''to'')
• Contribute to the conversation
• Expand upon
• Dipstick word
• Just-water connection
• Write a P.S., e.g.
• Perform an certain operation
• Attach (to)
• Calculate the sum
• Build an extension on
• Problem in focusing, for short
• Calculate a total
• Acquire more items for, as a collection