EXAMPLES FROM THE WEB FOR DIAMETRICALLY
His religion was designed to be diametrically opposed to Mahommedanism.
But they do not agree together; some of them are diametrically opposed to others.
Yet the feelings with which they regarded them were diametrically opposite.
Generally, with respect to crossing, the effects may be diametrically opposite.
Such inhabitants of the earth as are diametrically opposite to each other.
The interests of capital and labor are diametrically opposed to each other.
When this is used a diametrically opposite effect is produced.
All that each stood for was diametrically opposed to the other.
It will succeed because it is diametrically opposed to all I have expressed.
The reasons which they employed were diametrically opposite.
WORD ORIGIN
1630s, "completely" (opposed, contrary, etc.); see diametric. Mostly in figurative use; the two points that mark the ends of a line of diameter across a circle are opposite one another.