Merriam-Webster's Word of the Day for April 06, 2012 is:

carp • \KAHRP\  • verb
: to find fault or complain querulously

Examples:
Kate protested that her boss seemed to do nothing but carp and interfere, never praising or encouraging her.

"Critics have been carping endlessly that tonight's Oscars may be the most snooze worthy and least attractive to mainstream audiences in years." — From an article by Reed Tucker in The New York Post, February 26, 2012

Did you know?
You might guess that today's word is a descendant of the noun "carp," referring to a type of fish. That's a reasonable speculation, but the verb actually preceded the fish's name into the English language by approximately a century. Its origins are Scandinavian: it may be related to the Icelandic verb "karpa," meaning "to dispute" or "to wrangle," and beyond that perhaps to Old Norse "karp," meaning "boasting" or "arrogance." In the early 20th century, English speakers also coined a second noun "carp" (meaning "complaint") from this verb.