In the text of Sh'mot, the 10 "plagues" to which the Egyptians were subjected are described/called different things:
Blood is called about because the water was hit (makkeh) by Moshe and Aharon (7:17)
Frogs (7:27) Hashem says "anochi nogef" I plague (approx) and later (8:8) "d'var"
Lice (8:12) v'hach et (the dust was hit)
Animals -- mashlich ot (8:17) (send a sign)
Animal plague -- (9:5) ye'aseh (do this thing)
Boils -- no separate word
Hail (9:14) Magefotai, my plagues
Locusts -- Hamavet hazeh, this death (10:17)
Darkness -- no separate word
Death of Firstborn -- nega (11:1), lingof (12:23), hikkah (12:29 and v'hikkeiti, 12:12)
So most are not referred to by any word related to Makkah.
In Devarim 28, the land of K'na'an and the Children of Israel are threatened with "makotecha, v'et makot zar'echa, makot g'dolot) (pasuk 59) and makkah (61) and 29:21 -- makkot ha'aretz.
But stuck in the midst of all this, 28:60, there is "v'heishiv et kol madveh mitzrayim" -- the text chooses not to use a word related to makkah when discussing the events in Egypt!
The word "Makkah" only appears in the 5 books to refer to the punishment of the Children of Israel in Bamidbar, 11:33, lashes in Devarim 25:3 and the suffering mentioned in 28:61 -- never in relation to the plagues.
Only in Shmu'el I, 4:8 is there any such connection, though the reference is to "b'chol makkah bamidbar" with every Makkah in the desert (Rashi wrestles with this but doesn't explain this sudden choice of "Makkah" to describe the ten events).
By the time the text is discussed in Mishna Avot 5:4 (and the Tosefta Sotah and Avot D'Rabbi Natan) the term is Eser Makkot (Eser HAmakkot doesn't appear until Pesikta Zutrata and the Siddur of R. Amram Ga'on).
How do these ten events which are never called Makkot individually, and barely as a group suddenly become known by this shorthand? Are there other sources or other discussion which calls them all "ten makkot"?