内ない線せん番ばん号ごうMeaningsNoun1. extension numberKanji used内inside線line番place in a series号ID numberComposed of内ない線せんphone extension; indoor wiring; inner lineNoun番ばん号ごうnumber; series of digitsNounExamples1交こう換かん手しゅです。内ない線せん番ばん号ごうをどうぞ。This is the operator. Which extension would you like?