Like a portmanteau, but with a common sound at the end of one word and the start of the other.
Examples of Williamsisms include:

Train + entertainment = Trainertainment
Squid + disco = Squidsco
Queue + huge = Quege
by scratchysaurus December 14, 2010
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To disrespectfuly take advantage of another person's property, usually resulting in decrease of value upon return.
Thanks for taking care of my trailor and not williamsing it!
by Bubbacan August 21, 2009
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blatantly lying or fabricating a story
She was totally Brian Williamsing. Leo DiCaprio did not deliver a pizza to her door last night.
by caseythewordmaker February 9, 2015
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