Quick Definition
a falling, a fall
Strong's Definition
a crash, i.e. downfall (literally or figuratively)
Derivation: from the alternate of G4098 (πίπτω);
KJV Usage: fall
Thayer's Greek Lexicon
πτῶσις, πτώσεως, ἡ (πίπτω, perfect πέπτωκα), a falling, downfall: properly, τῆς οἰκίας, Mat_7:27 (πτωσεις οἴκων, Manetho, 4, 617); tropically, εἰς πτῶσιν πολλῶν (opposed to εἰς ἀνάστασιν), that many may fall and bring upon themselves ruin, i. e. the loss of salvation, utter misery, Luk_2:34, cf. Rom_11:11. (The Sept. chiefly for ξΗβΕΜτΘδ, plague, defeat.)
Mounce Concise Greek Dictionary
πτῶσις ptōsis 2x
a fall, crash, ruin, Mat_7:27 ;
met. downfall, ruin, Luk_2:34
Abbott-Smith Greek Lexicon
πτῶσις , -εως , ἡ
( < πίπτω ),
[in LXX chiefly for H5063 , H4658 , and cogn . forms;]
a falling, fall ( Plat ., Plut ., al. ): Mat_7:27 ; metaph ., Luk_2:34 .†
Liddell-Scott — Intermediate Greek Lexicon
πτῶσις πτῶσις, εως, [Etym: πίπτω, πέπτωκα] "a falling, fall", Plat. Lat. casus, the "case" of a noun, Arist.
STEPBible — Tyndale Abridged Greek Lexicon
πτῶσις, -εως, ἡ
(πίπτω), [in LXX chiefly for נֶגֶף, מַפֶּלֶת, and cogn. forms ;]
a falling, fall (Plat., Plut., al.): Mat.7:27; metaphorically, Luk.2:34.†
(AS)