There are several stations in Osaka which you can say terminal stations. The busiest terminal is Osaka station which is used only by JR. Then, Umeda station which is adjacent to Osaka station is used by private railway companies Hankyu and Hanshin, and Osaka metro. Then, Osaka Namba station which is used by Kintetsu and Hanshin, Namba station used by Nankai and Osaka metro. JR also has JR Namba station which used to be Minatomachi station till 1994. It is little bit away from the Namba station.
Tennoji station is the third terminal station in Osaka, located in the south of these two terminals. There are 3 JR lines using this station. Osaka loop line, Yamatoji(Kansai main) line and Hanwa line. Then two Osaka metro lines, Midosuji and Tanimachi lines. Private railway Kintetsu also has its terminal nearby but the name is Osaka Abenobashi station.
Interesting fact of Tennoji station is that limited express Haruka which connects Kansai airport and Kyoto station stops at Tennoji but does not stop at Osaka station. Instead of stopping at Osaka, the limited express stops at Shin-Osaka station where you can change to Shinkansen.
Tennoji station is the only JR station in Osaka which has bay platform; dead end platform which you can see in big cities in Europe. Bay platform is rare in Japan and JR Namba station used to be bay platform until 1994 when it was called Minatomachi station.