1. Whether one or the other.

Nuttall's Standard dictionary of the English language By Nuttall, P.Austin

• whathever,
• whicever,
• witchever,
• whcihever,
• whichver,
• whethever,
• wichever,
• whickeer,
• qhichever,
• ahichever,
• shichever,
• ehichever,
• 3hichever,
• 2hichever,
• wgichever,
• wbichever,
• whichwver,
• whicheever,
• Whichewer,
• which ever

The adjective form of the word "whichever" is "whichsoever".

The plural form of "whichever" remains the same, as it is an indefinite pronoun that does not change in its plural form.

The singular form of the word "whichever" is "whichever".