Engagement gift (both words suit this puzzle's theme)

Question:

Answer:

DIAMONDRING

Length:

Similar Crossword Questions:

Number of times this puzzle's theme word appears diagonally in the grid (to complete the puzzle, shade those words plus the Down answers that begin where they meet)
Attendance check, and a hint to the puzzle theme in the first words of the starred answers
Place to fix this puzzle's theme words?
What this puzzle's theme words aim to do
What the self-contradictory words found in this puzzle's theme answers are examples of
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Question not asked in this puzzle's theme words
Famous last words (and homophonically, a hint to this puzzle's theme)
Like the theme words in this puzzle?
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Alternative words used as alternatives for each other in this puzzle's theme answers
Theme word inside this puzzle's theme words
"Magic" words that are the theme of this puzzle
Place to use this puzzle's theme words?
Personalized album, and this puzzle's theme
Type of gear on which the letters in this puzzle's nine theme squares are arrayed
Onetime winner of all the awards in this puzzle's theme
Marketing ploy, and a hint to this puzzle's theme
Allot, in this puzzle's theme
Simple code that uses a half-alphabet shift and that's the key to this puzzle's theme
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Each of the numbers in this puzzle's theme
Oxford American Dictionary's 2012 word of the year, and the key to this puzzle's theme
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