来自古英语pitha,树心，木髓，来自West-Germanic*pithan,核，词源同pit.引申词义核心，精髓。

1. the pith of her argument

她论据的核心

2. Using a sharp knife, cut away the pith and peel from both fruits.

用一把锋利的刀削去两种水果的外皮和中果皮。

3. Both the rubber and the pith ball are negatively charged.

这时,橡胶棒和木髓球两者都带负电荷.

4. The pith of this stemlike stele appears rather strongly like collenchyma tissue.

茎状中柱的髓显得颇强健,像厚角组织.

5. Major Shairpe, much spruced up and wearing a pith helmet , arrived on the dot of nine.

谢普少校打扮得整洁多了,戴着一顶编织着木髓的钢盔, 正好九点来到.