%assentation%

n. [ L. assentatio. See Assent, v. ] Insincere, flattering, or obsequious assent; hypocritical or pretended concurrence. [ 1913 Webster ]

Abject flattery and indiscriminate assentation degrade as much as indiscriminate contradiction and noisy debate disgust. Ld. Chesterfield. [ 1913 Webster ]