n.四位组；四分体；四元基
Abnormal development was observed at tetrad and mature embryo sac. 在四分体和成熟胚囊时期观察到了异常发育现象。
The megaspore mother cell meiosis to form a linear megaspore tetrad. 大孢子母细胞减数分裂产生直线形大孢子四分体。
n.四德拉克马银币(古希腊银币名)
