Here is the relevant part of the entry, complete with links to the texts at Perseus:
II. as fem., woman,Pi.P.4.98, Hdt.1.60, Isoc.18.52, Arist.EN1148b20; contemptuously, of female slaves, Antipho1.17, Is.6.20, etc.; with aIn the text from Isocrates for example, the words τὴν ἄνθρωπον show unambiguously that ἄνθρωπος anthrōpos is grammatically feminine. But, although Marlowe refers to the "Liddell & Scott Lexicon" entry for this word, he does not seem to be aware of this usage of the word as grammatically feminine.
[p. 142]sense of pity, D.19.197.
Now I accept that these feminine occurrences are not in biblical texts, and at least many of them are from long before the New Testament period. But that does not make them entirely irrelevant, and certainly does not justify a writer on this subject denying their existence. But there is at least one case in biblical Greek of ἄνθρωπος anthrōpos in the plural, and without specified grammatical gender, referring to a group which is explicitly of women only: καὶ ψυχαὶ ἀνθρώπων ἀπὸ τῶν γυναικῶν..., Numbers 31:35 LXX.
I found this reference from a paper by David Clines, the well-respected editor of the authoritative work The Dictionary of Classical Hebrew, concerning the Hebrew word אָדָם 'adam. (Thank you, David R, for drawing this paper to my attention.) This Hebrew word corresponds quite closely in meaning to Greek ἄνθρωπος anthrōpos, and they are often translational equivalents. I would recommend anyone interested in the meaning of ἄνθρωπος anthrōpos to read Clines' paper.