Commercial Fixed Wing
Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument
Communication Breakdown; Confusion; Situational Awareness
ATC Issue All Types; Deviation / Discrepancy - Procedural Clearance; Ground Incursion Taxiway
Air Traffic Control Issued New Clearance; Flight Crew Became Reoriented
Chart Or Publication; Human Factors
On  taxi out of Austin for [Runway] 17R; Ground Control gave us Charlie 2; Charlie; [Runway] 17R. We had briefed at the gate possibly ramp to Charlie; then [Runway] 17R and also Golf 3; Golf; Charlie; [Runway] 17R. With the instructions from Ground; we both heard Golf 3 to [Runway] 17 Right. We turned left after pushed back on a 180-turn; we were headed out Golf 3; and we saw traffic on our right on Charlie and stopped. We asked Ground if they knew about the traffic; and at that time he told us we were taxiing the wrong direction. He said he gave us Charlie 2. We had to look at the 10-9 page and see that there is no Charlie 2. So we were confused as to where he wanted us to taxi. We got a second confirmation on the taxi instructions and headed to 17R with no further incidences.  The Jepps 10-9 does not indicate C2. [We need a] correction to the 10-9 page. The parking and gate page shows C2.
After pushback; Ground gave us taxi instructions C2-C-Runway 17R. We heard G2 and should have inquired about missing G Taxiway in assignment. Starting a turn onto G Taxiway we learned of the mix-up and checked the taxi diagram but didn't see C2 on the 10-9. After getting confirmation from Ground we taxied G-G3-into the ramp then C2-C-Runway 17R.As the Pilot Monitoring I should have asked more questions regarding our clearance to clarify; but I would like to see C2 on the 10-9 if ATC is going to use C2 instead of ramp phraseology.
Flight crew reported a taxi deviation occurred when Ground referenced a taxiway not charted on their 10-9 page.