UPDATED: The term [cholangiogram] is composed by the combined root terms [-chole-] derived from the Greek word [χολή] (cholí) meaning "gall" or "bile, and the root term [-angi-], also derived from the Greek  [αγγείο] (angeío), meaning "vase", or "vessel"letter. The suffix [-(o)gram] evolved from the Greek word [γράμμα] (grámma) , meaning "letter", although today we use it to mean "examination of". For more information on this suffix, click here. The term [cholangiogram] therefore means "examination of a bile vessel". 

A cholangiogram is the fluoroscopic imaging of a bile duct. To do this a radio-opaque dye is introduced in the bile system and a series of X-ray images are taken of the hepatobiliary tree. Today the examination can be performed intraoperative in conjunction with a cholecystectomy using a C-arm fluoroscope

The accompanying video (without sound) shows an intraoperative normal cholangiogram.

Video courtesy of YouTube, Mr. Andrew Smith and the Yorkshire Gallstone Clinic.