subtend

• vt. 对向；包在叶腋内

sub-,在下，向上，-tend,延展，词源同 tend,extend.用于几何学术语指对向弧，对向角。

subtend (v.)

1560s, from Latin subtendere "to stretch underneath," from sub "under" (see sub-) + tendere "to stretch" (see tenet). Related: Subtended; subtending.

1. In the daisy family the numerous bracts which subtend the inflorescence are known as an involucre.

在菊科植物中,苞片数目多而聚生在花序外围,称为总苞.

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