adj.無痛的；不痛的

The scan is safe, quick and painless. 掃描過程是安全、快速和無痛的。

The most common presenting symptom is a painless mass. 主要的臨床癥狀為無痛性腫瘤。

Walking is an easy, painless and powerful form of exercise. 走路是一種簡單、不痛苦又有效的運動。

adv.(口語)不難地；不費力地