[cf. Ger. Hahnen-tritt.] The opaque speck or germinal vesicle on the surface of the yolk in an impregnated egg. Also, in earlier use, Cock-treading.
1573. Art of Limming, 3. Take the whites of egges not breaking them in anye wise, but take out the cocketreading.
1654. Gayton, Pleasant Notes, II. ii. Cock tread.
1655. Queen’s Closet Opened, 47 (D.). Take the cock-treading of twelve eggs and the white of one egge.
1682. G. Hartman, Preserver & Restorer of Health, 86. Take the Cock-tread, and put it into the shell again.
a. 1825. Forby, Voc. E. Anglia, s.v. Cock’s-tread.
