The primary headword is the present active infinitive of e(stia/w; also glossed in the entry is its present middle/passive infinitive.
[1] From "to feed..." up to this point the entry = Synagoge epsilon869; Photius, Lexicon epsilon2024. The initial syntactical information is added from a syntactical lexicon, for which Adler cites the Syntacticum Gudianum and the syntactical lexicon of Codex Laurentianus 59.16; cf. also Anecdota Graeca (Bekker) 141.25. Hesychius defines a number of different forms and derivatives of the verb with similar glosses: epsilon6391, epsilon6394, epsilon6396, epsilon6399, epsilon6400.
[2] From the scholia to Aristophanes, Clouds 1354, where ei(stiw/meq' occurs.
[3] Aristophanes, Thesmophoriazusae 942 (web address 1), with comments from the scholia. The form of the verb here is present active participle, nominative masculine singular. The active verb is normally construed with an accusative, and the scholiast's statement to the contrary may be based on an misapprehension about the passage, which in full (941-2) runs i(/na mh\ ... ge/lwta pare/xw toi=s ko/racin e(stiw=n "Lest I provide [a source of] laughter to the crows while feasting [them]." The dative ("to the crows") seems to follow primarily on pare/xw ("I provide"), which normally governs a remote object in the dative. One could argue, however, that the dative is also construed with "feasting" apo koinou.