The articulation of the radius and ulna in the arm is a pivot joint.

手臂桡骨和尺骨的连接关节是一个枢轴关节。

youdao

However, as Sprint embraces retail consumer electronics, it will see that -- on some level -- the enemy is itself, a familiar position for a company that has juggled hosting the wireless networks of Helio, Disney Mobile, its cable joint venture Pivot and its own Boost.

ENGADGET: Switched On: The WiMAX Window (Part 2)

That joint venture, called Pivot, dissolved last year when the companies couldn't agree on pricing and marketing strategy, according to people familiar with the matter.

WSJ: Cox Plans to Launch a Cellular Network

The same companies created a separate joint venture with Sprint in 2005, dubbed Pivot, that offered cellphone service in about 30 markets by the time it stopped marketing late last year amid low demand.

WSJ: Comcast, Time Warner Cable in Wireless Talks