| 释义 |
focaloid Math.|ˈfəʊkəlɔɪd|
[f. as prec. + -oid.]
A shell, in general indefinitely thin, bounded by two confocal ellipsoidal surfaces.
1879Thomson & Tait Nat. Phil. §494 The attraction of a homogeneous solid ellipsoid is the same through all external space as the attraction of a homogeneous focaloid of equal mass coinciding with its surface. |