What is "metapuzzle"

n. A compound puzzle formed by several lesser puzzles. In contrast to a regular puzzle, a metapuzzle is missing data that is essential to solving it, and which can only be obtained by solving other sometimes entirely unrelated puzzles. Metapuzzles are frequently used in puzzlehunt.

A metapuzzle is a puzzle that unites several puzzles that feed into it. For example, five puzzles that had the answers BLACK, HAMMER, FROST, KNIFE, and UNION would lead to the metapuzzle answer JACK, which combines with all of those words to make new words and phrases.

A "meta-meta" unites several metapuzzles. So if that metapuzzle answer JACK was alongside three metapuzzles with the answers TEN, QUEEN, and ACE, the meta-meta answer would be KING, the remaining card in an ace high straight.

Metapuzzles are frequently found in puzzlehunts.

The structure of a metapuzzle often makes it possible to guess, with a greater or lesser degree of certainty, the solutions to the puzzles that feed into it without solving them. This technique is called backsolving. For instance, in the above example, after solving the puzzles whose answers were BLACK, HAMMER, FROST, and KNIFE, and the metapuzzle answer JACK, a backsolver might, instead of solving the fifth puzzle, correctly guess UNION as its answer simply based on the knowledge that it must form a word or phrase with JACK. Backsolving is not infallible; the same backsolver might incorrectly guess SPRING-HEELED as the answer just as easily as correctly guessing UNION.

The meta prefix has been repurposed for the unrelated meta crosswords, which are not metapuzzles. A meta crossword is a puzzle which has an extra extraction step to extract a final answer after the crossword is completed. Most crosswords in a puzzlehunt are like this, but they are not called meta crosswords in the context of a hunt, as that would be confusing.