imperforate
/ɪmˈpɜːfərət/adjective
1- not perforated, in particular无孔的, 尤指：
1.1
- Anatomy & Zoology lacking the normal opening【剖, 动】无孔的, 闭锁的：
unicellular spores of these parasites have an imperforate wall.
这些寄生虫的单细胞孢子有一层无孔壁。
1.2
- (of a postage stamp or a block or sheet of stamps) lacking perforations, especially as an error（邮票）无齿孔的。