Webster's Revised Unabridged Dictionary · 1913

Transubstantiate

Transubstantiate , transitive verb

[Late Latin transubstantiatus, past participle of transubstantiare to transubstantiate; Latin trans across, over + substantia substance. See Substance.]

1.
To change into another substance. [Rare]
The spider love which transubstantiates all, And can convert manna to gall. — Donne
2.
(R. C. Theology) To change, as the sacramental elements, bread and wine, into the flesh and blood of Christ.