savoir-faire

noun

1. knowledge of just what to do in any situation; tact.

noun

1. the ability to do the right thing in any situation

n.“instinctive knowledge of the right course of action in any circumstance,” 1815, from French, literally “to know (how) to do,” from savoir “to know” (from Latin sapere; see sapient) + faire (from Latin facere; see factitious). French also has savoir-vivre “ability in good society; knowledge of customs in the world.”