A weasel word (also, anonymous authority) is an informal term for equivocating words and phrases aimed at creating an impression that something specific and meaningful has been said, when in fact only a vague or ambiguous claim has been communicated.
For example, an advertisement may use a weasel phrase such as "up to 50% off on all products".
See more at http://en.wikipedia.org/wiki/Weasel_word
“Weaseling out of things is important to learn. It’s what separates us from the animals … except the weasel. “