阳螺旋，柱螺纹。的英文

• male screw

• 阳:    the sun
• 螺旋:    corkscrewspin; screw; spiral ...
• 螺纹:    screw thread; flight; helica ...
• 阳螺纹:    external screw thread; external thread; male screw thread; pin and box; pin thread; pin-to-box pipe; pin-to-box sub; positive thread
• 阳螺旋:    positive helicity