"Amicable"

When:

Lookups on Merriam-Webster.com spiked on May 10, 2011.

Why:

Arnold Schwarzenegger and Maria Shriver announced that they were "amicably separating" after 25 years of marriage.

Amicable means "showing a polite and friendly desire to avoid disagreement and argument."

The word traces back to the Latin amicus, meaning "friend."