Easton's Bible Dictionary (1897)
Lat. pietas, properly honour and respect toward parents (1 Tim. 5:4). In Acts 17:23 the Greek verb is rendered “ye worship,” as applicable to God.
Smith's Bible Dictionary (1863)
This word occurs but once in the Authorized Version: “Let them learn first to show piety at home,” better “toward their own household” or family. (1 Timothy 5:4) The choice of this word here instead of the more usual equivalents -of “godliness,” “reverence,” and the like, was probably determined by the special sense of pietas, as “erga parentes,” i.e. toward parents.
Hastings' Dictionary of the Bible (1898)
PI'ETY occurs only once in our version, 1 Tim 6:4, where it denotes the reverence which children owe their parents.