Verb 1. To drink far in excess of all other wedding reception participants, guests, officiants, or attendants at an open bar and to actively disrupt the celebratory event by means cutting in line to the open bar, blocking access to the open bar, being excessively gregarious, loud, insulting, self-depricating, and ending the night by being completely and utterly inebriated to the point of committing an unspeakable act such as vomiting all over one's self and others while in a heavily occupied passenger or commuter vehicle.
Verb 2. To be "that guy," at a wedding.
Present tense: To Smith. Past Tense: Smithed.
See Also: Jackass
That wedding would have been great had that tall dude with spikey hair not Smithed it.