Assimulatio, Verbale. Plin. A dissembled countenaunce.
Lewis and Short: Latin dictionary
assĭmŭlātĭo (better ads-, not assĭ-mĭlātĭo; v. assimulo fin.), ōnis, f. [id.], an assimilating.I.A being similar, similarity, likeness: prodigiosa adsimulatio, Plin. 11, 49, 109, 262.—II. In rhet., a feigned adoption of the opinion of one's hearers: est (adsimulatio) cum id, quod scimus facile omnes audituros, dicimus nos timere, quomodo accipiant; sed tamen veritate commoveri, ut nihilo setius dicamus, Auct. ad Her. 4, 37, 49.—III.A comparison of one thing with others: dolosa, Dig. 2, 18, 19, 24; Cod. Th. 16, 2, 18.