LONDON — Britain’s media are in a meltdown and its government is gaffe-prone, so Oxford Dictionaries has chosen an apt Word of the Year: ‘‘omnishambles.’’

Oxford University Press on Tuesday crowned the word — defined as ‘‘a situation that has been comprehensively mismanaged, characterized by a string of blunders and miscalculations’’ — its top term of 2012.

Each year Oxford University Press tracks how the English language is changing and chooses a word that best reflects the mood of the year. The publisher typically chooses separate British and American winners. This year’s American champion is ‘‘gif,’’ short for graphics interchange format, a common format for images on the Internet.

The editors said gif was being recognized for making the crucial transition from noun to verb, ‘‘to gif’’: to create a gif file of an image or video sequence, especially relating to an event. And, inevitably, to share it online. Cute kittens, Olympic champions, President Obama — they’ve all been giffed.

Coined by writers of the satirical television show ‘‘The Thick of It,’’ omnishambles has been applied to everything from government PR blunders to the crisis-ridden preparations for the London Olympics.

Oxford University Press lexicographer Susie Dent said the word was chosen for its popularity as well as its ‘‘linguistic productivity.’’