The Greek word κτίσεως is declined in the genitive case, singular number from the lemma κτίσις. The lemma κτίσις, as Thayer notes,1 can refer to the act of creation, some individual thing created (i.e., a creature, equivalent to κτίσμα), or the sum of all individual things created.
English translations of Col. 1:15 vary between the last two meanings, whether the apostle is referring to “every creature” or “all creation.”
...the anarthrous πᾶσα κτίσις does not mean the whole creation, or everything which is created (Hofmann), and consequently cannot affirm the category or collective whole to which Christ belongs as its first-born individual (it means: every creature...
He further argues that “the article would necessarily be added”3 if it were to be understood as “the entire creation” or “all creation.”
On the other hand, Alford remarked,4
the first-born of all creation (such, and not ‘every creature,’ is the meaning (so I still hold against Ellic[ott]. But see his whole note on this passage, as well worth study): nor can the strict usage of the article be alleged as an objection: cf. below, Colossians 1:23, and Ephesians 2:21 note: the solution being, that κτίσις, as our word ‘creation,’ may be used anarthrous, in its collective sense.
Alford cites two scriptures as proof that the article is not required for the sense “all creation”: Col. 1:23 and Eph. 2:21. The problem with both of these scriptures is that there are textual variants which essentially nullify his argument.5 Alford seems to disfavor the translation “every creature” because it seems to reckon the Son as a creature (as Arians would contend). However, this is not a necessary consequence of such a translation.
Alford, Henry. The Greek Testament. Vol. 3. Boston: Lee, 1878.
Meyer, Heinrich August Wilhelm. Critical and Exegetical Handbook to the Epistles to the Philippians and Colossians, and to Philemon. Trans. Moore, John C. Ed. Dickson, William P. New York: Funk, 1889.
Wilke, Christian Gottlob. A Greek-English Lexicon of the New Testament: Being Grimm Wilke’s Clavis Novi Testamenti. Trans. Thayer, Joseph Henry.Ed. Grimm, Carl Ludwig Wilibald. Rev. ed. New York: American Book, 1889.
1 p. 363
2 p. 225
3 ibid., footnote 1
4 p. 202
5 Col. 1:23: «ἐν πάσῃ τῇ κτίσει» vs. «ἐν πάσῃ κτίσει»; Eph. 2:21: «πᾶσα ἥ οἰκοδομὴ» vs. «πᾶσα οἰκοδομὴ»