C. Parallels of -culum and Accessory Suffixes
Among -culum words, we find cenaculum having an accessory form cenatio that has, not the verbal idea, but the genuine meaning of place for eating, while cenaculum has lost its literal meaning and taken a more general signification: vel cubiculum grande vel modica cenatio [sit] quae plurimo sole lucet, Plin. Ep. 2, 17, 10; nos ampliores triginta vidimus in cenatione quam Callistus exaedificaverat, Plin. 36, 7, 12; ubi cubabant, cubiculum, ubi cenabant, cenaculum vocitabant; posteaquam in superiore parte cenitare coeperunt superioris domus universa cenacula dicta, Varro, L. L. 5, 162.
On the stem curro there are three nouns, all signifying “a running”: exercent sese ad cursuram, Most. 861; ibi cursu, luctando sese exercebant, Bacc. 428; unum curriculum face, Trin. 1103. A use of curriculum with exerceo would parallel the first two examples, but in such a case it takes on the meaning of place (running course): cum athletae se exercentes in curriculo videret, C. 27.
In the same paragraph deversorium and deverticulum are used of the same place: ut in deversorium eius vim magnam gladiorum inferri clam sineret, Liv. 1, 51; cum gladii abditi ex omnibus locis deverticuli protraherentur, Liv. 1, 51.
Feretrum and ferculum both are used depending on suspensa in the two following examples, but mean different kinds of “instruments for carrying”: quis opima volenti dona Iovis portet feretro suspensa cruento, Sil. 5, 168; spolia ducis hostium caesi suspensa fabricato ad id apte ferculo gerens in Capitolium ascendit, Liv. 1, 10, 5.
The stem cerno (sift) forms two nouns which both mean a sieve, although the use of them side by side indicates that there must be some difference; as there are no other examples of incerniculum, this difference cannot be discovered: in torcularium quod opus est cribrum unum, incerniculum unum, Cato, R. R. I, 13, 3; caseum per cribrum facito transeat in mortarium, Cato, R. R. 76, 3.
In the following examples, spiramen and spiracula are both used to mean “breathing holes” in the earth or universe, while spiramenta is applied to the cells in a beehive:
sunt qui spiramina terris
esse putent magnosque cavae compages hiatus,
Lucan, 10, 247;