Lexicon :: Strong's G4073 - petra

πέτρα, πέτρας, ἡ, from Homer down; the Sept. for סֶלַע and צוּר; a rock, ledge, cliff;
a. properly: Matthew 7:24; Matthew 27:51, 60; Mark 15:46; Luke 6:48; 1 Corinthians 10:4 (on which see πνευματικός, 3 a.); a projecting rock, crag, Revelation 6:15f, rocky ground, Luke 8:6, 13.
b. a rock, large stone: Romans 9:33; 1 Peter 2:8 (7).
c. metaphorically, a man like a rock, by reason of his firmness and strength of soul: Matthew 16:18 (some interpretations regard the distinction (generally observed in classic Greek; see the commentaries and cf. Schmidt, Syn., chapter 51, §§ 4-6) between πέτρα, the massive living rock, and πέτρος, a detached but large fragment, as important for the correct understanding of this passage; others explain the different genders here as due first to the personal then to the material reference. Cf. Meyer, Keil, others; Green, Critical Note on John 1:43).

BLB Scripture Index of Thayer's