Wikipedia
In ovo
In ovo is Latin for in the egg. In medical usage it refers to the growth of live virus in chicken egg embryos for vaccine development for human use, as well as an effective method for vaccination of poultry against various Avian influenza and coronaviruses. During the incubation period, the virus replicates in the cells that make up the chorioallantoic membrane.
Usage examples of "in ovo".
And, more importantly, she would be gone from the spot to which she still hoped Oscar would come, following her across the In Ovo.
At that juncture the circle, its power no longer needed as a conduit to carry the analogues back into its reservoir, would turn off those currents and turn its attention to conveying the Reconciler through the In Ovo.