来自拉丁语lacuna,洞，小坑，词源同lake.后用于指书写文档上的空格或缺漏符号。

1. Reasons of forming first cracks were foundry lacuna, impurity gathering , lard exiting.

铸造缺陷 、 杂质元素偏聚和夹杂物的存在是形成早期裂纹源的原因.

2. Results 42 cases were successfully, detain 7 - 16 days without lacuna out.

结果42例置管均成功, 留置时间7-16天,无管道脱出.

3. There was so much very deep lacuna in his crude big hands.

粗糙的大手上一道道很深的裂口.

4. It is this political lacuna that makes optimists about Brazil so impatient.

正是这块政治上的疤痕使得对巴西的前景很有信心的乐天派们变得像热锅上的蚂蚁,如坐针毡.

5. Objective To investigate the clinical value of transcranial Doppler ( TCD ) in cerebral lacuna infarct.

目的探讨经颅多普勒 ( TCD ) 检查在脑腔隙性梗死中的应用价值.