The headword, illustrated by the first quotation given, is the present active infinitive of the contract verb fla/w, I crush; see generally LSJ s.v.
[1] The glosses, from the verbs qla/w and tu/ptw, respectively, are both present active infinitives; see LSJ s.vv. The headword is identically glossed in Photius' Lexicon (phi216 Theodoridis); cf. Etymologicum Gudianum phi551.59, Etymologicum Magnum 795.35 (Kallierges), and De Stefani, p. 66. (Different glossing in Hesychius phi267 s.v.)
[2] From the iambic canon on Epiphany (Nauck 2.25, p. 112) attributed to Saint John of Damascus (c.676-750; Louth, p. 5). The gruesome metaphor employed, crushing the head of a wild beast, is imagery for overcoming temptation and evil.
[3] Aristophanes, Plutus [Wealth] 782-5 (web address 1): soon after the whole world's distribution of wealth has been reversed, Chremylus delivers this gripe about his poor farmer friends comprising the chorus. [In her critical apparatus Adler reports that ms F omits the Aristophanic extracts from the entry; that mss AV omit ga\r (for), they nudge you; that ms A reads filw=si, which is probably an error; and that the last participial phrase here and then the rest of the entry is omitted by ms G.]
[4] Aristophanes, Peace 500 (web address 2): Hermes issues this imprecation (literally, go to the crows) to the men of Megara. [Adler reports that some of the manuscripts struggled with the second person plural, future indicative e)rrh/sete (you will be gone (slowly, to your peril)); that ms A reads e)rh/sete (which is otherwise unattested) and places ai above the final epsilon to suggest the emendation e)rh/setai, he/she/it will inquire; and that here ms V transmits eu(rh/setai, he/she/it will discover.]