Quadrennial occasion celebrated by this puzzle's theme entries

Question:

Answer:

LEAPDAY

Length:

Similar Crossword Questions:

Just making things up, or a synonym for a three-word phrase describing this puzzle's theme entries
Second of a pair of letters swapped six times in this puzzle's theme entries
Where to find the theme entries of this puzzle, briefly
It can follow the last word of this puzzle's theme entries
What each of this puzzle's theme entries contains
Period that ends Nov. 3rd, requiring a shift, and letters that shift in this puzzle's theme entries
Nickname for the three-letter abbreviation hidden in this puzzle's theme entries
Word hidden in this puzzle's theme entries
What are featured in the theme entries of this puzzle
What this puzzle's theme entries have
Office building problem that's a hint to this puzzle's theme entries (see their last three letters)
Many people get one in the summer (and so do this puzzle's theme entries)
What this puzzle's theme entries are
There's one at the beginning of each of this puzzle's four theme entries
Levels that are split in this puzzle's theme entries
Act affectedly, and what this puzzle's theme entries do?
Gym gear hidden in this puzzle's theme entries
Like fish for fish & chips -- or this puzzle's four theme entries
What the names in this puzzle's theme entries begin with
People who bring you this puzzle's theme entries
First of a pair of letters swapped six times in this puzzle's theme entries
Like the four theme entries in this puzzle, as it were
The three of this puzzle's theme entries
Physical principle whose equation explains the changes in this puzzle's theme entries
Event celebrated in this puzzle, and an example of how the theme works