abbr. 航天器-登月舱适配器（spacecraft-lunar module adapter）；[计]服务等级协议（service level agreement）；运动文学协会（Sport Literature Association）；二语习得（second language acquisition）
Aluminum, being less dense than steel, has greater sound radiation, and yet the alloy-bodied SL summons a lush, refined quiet in the cabin to rival a fixed-roof car.
Both new SL-Series cameras feature a high-quality 27mm wide-angle Samsung lens with 5x optical zoom, delivering significant flexibility when compared to a traditional 3x optical zoom, 35mm lens.