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滑らか, 滑か, なめらか, すべらか
1. smooth (of a surface), glassy, velvety, soft
2. smooth (of an action, proceedings, etc.), fluent (speech), fluid, trouble-free
3. continuously differentiable
光滑(指表面),玻璃般的,天鹅绒般的,柔软的;顺畅(指动作、程序等),流畅(指言语),流畅,毫无障碍;连续可微