GRC
Bailly
ος, ον [ᾰν] c. ἀπλανής, BABR. 50, 20 ; SYMM. Job 12, 20.
Bailly 2020 Hugo Chávez Gérard Gréco, André Charbonnet, Mark De Wilde, Bernard Maréchal & contributeurs / Licence Creative Commons Attribution - Pas d'Utilisation Commerciale - Pas de Modification — « CC BY-NC-ND 4.0 »
LSJ
ον, that cannot go astray or err, LXX Jb. 12.20, Babr. 50.20, POxy. 237 vi30 (ii AD).
Liddell-Scott-Jones, Greek-English Lexicon (9th ed., 1940)
Pape
= ἀπλανής, Clem.Al.; Schol. Soph. O.R. 472, unverirrt.
Pape, Griechisch-deutsches Handwörterbuch (3. Aufl., 1914)
TBESG
that cannot go astray , (Babrius Fabularum Scriptor) (ML)
Translators Brief lexicon of Extended Strongs for Greek based on Abbot-Smith, A Manual Greek Lexicon of the New Testament (1922) (=AS), with corrections and adapted by Tyndale Scholars