Process by which an element's atomic number may be reduced, and a hint to this puzzle's theme

Question:

Length:

Similar Crossword Questions:

Seasonal workers (and a short hint to this puzzle's theme)
"Shut up!" ... or a phonetic hint to this puzzle's theme
School cafeteria fare ... and a hint to this puzzle's theme
Certain spring training matches, and a hint to this puzzle's theme
Sailor's OK, and a phonetic hint to this puzzle's theme
Ubiquitous arcade game message, or a hint to this puzzle's theme
Special CD release ... or a hint to this puzzle's theme
Pleasure trip, and a hint to this puzzle's theme
Playoff series finale ... or an apt title for this puzzle considering the number and length of its theme entries
Something to do on Arbor Day (and a hint to this puzzle's theme)
"That's repulsive!" ... or a hint to this puzzle's theme
Party with too many dudes... or a hint to this puzzle's theme
Press time (and a hint to this puzzle's theme)
Nanobot's hypothetical ability, and the process that's overtaken this puzzle's theme answers
First name of a civil rights activist who would turn 85 today, and whose adopted last name is a hint to this puzzle's theme
"Never mind," and a hint to this puzzle's theme
"Have a nice day" response, and a literal hint to this puzzle's theme
Hidden element in this puzzle's theme
Postseason gridiron game, and a hint to the puzzle theme found in starred answers
Sitcom whose first episode was titled "Movin' In" (and a hint to this puzzle's theme)
2014 NBC comedy starring David Walton ... and a hint to the puzzle theme which is ___
''Let it go!'' (and hint to this puzzle's theme)
Element of surprise in this puzzle's theme answers
Staff members (and a hint to this puzzle's theme)
New element in each of this puzzle's theme answers