92. In the discussion of declensions some phonetic peculiarities must not be overlooked:--
(1) In the nom. pl. of the 2d declension, a stressed ẹ, followed in the next syllable by final -ị, would regularly give ị (cf. § 27, 1); but the ẹ is preserved by the analogy of the nom. and obj. sg. and the obj. pl.: _capĭllī_ ＞ cabẹl, _mĭssī_ ＞ mẹs, _quētī_ ＞ quẹt, _sērī_ ＞ sẹr. We do, however, find cabil, and (perhaps by analogy) auzil ＜ _aucĕllī_.
(2) In the nom. pl. of the 2d declension, a c or g before the final -ị would regularly be palatalized (cf. § 55, C, G); but it is preserved from palatalization by the analogy of the other three forms: _amīcī_ ＞ amic, _lŏngī_ ＞ lonc.
(3) For the development of a t between a palatal or an n and a final s, see § 82, S: _annos_ ＞ anz, _fīlios_ ＞ filz.
(4) For the simplification of final scs, sts to cs, ts, see § 78, 2: ✱_bŭscus?_ ＞ bǫcs, _trīstes_ ＞ tritz.
(5) For the history of _-arius_ and _-tōrius_, see § 23, 1 and § 73, Ry, 1.
93. (1) Nouns whose objective singular ended in s were invariable in the earlier part of the literary period; _bracchium_ ＞ bratz, _cŏrpus_ ＞ cǫrs, _imperatrīcem_ ＞ emperairitz, _fascem_ ＞ fais, _latus_ ＞ latz, _lūcem_ ＞ lütz, _mĭssum_ ＞ mẹs, _nasum_ ＞ nas, _ŏpus_ ＞ ǫps, _ŭrsum_ ＞ ọrs, _pĭscem_ ＞ pẹis, _pĕctus_ ＞ pęitz, _prĕtium_ ＞ prętz, _tĕmpus_ ＞ tems, _vĕrsum_ ＞ vęrs, _vīsum_ ＞ vis, _vōcem_ ＞ vọtz. Later, however, a plural (originally obj. pl.) was made for such words by adding -es, generally at a time when final ts had been reduced to s (§ 64): brasses, cǫrses, mẹsses, pẹisses, vęrses; examples occur as early as the end of the 12th century.
(2) Other invariable nouns are midons, sidons, and often laus and rẹs; the last two sometimes have an objective lau, rẹ. Midons comes from the Church Latin _mī dŏmĭne_, which was popularized by the substitution of the Provençal don for _dŏmĭne_ and the addition of the nom. -s; the term was transferred from religious to feudal, and thence to amatory use, and came to mean ‘my lady.’ _Mi domina_ was common in Church Latin. Sidons is formed on the model of midons.
(3) For nouns in tš, see § 63, (1): ✱_disdūctum_ ＞ desdüg, _frūctum_ ＞ früch, _gaudium_ ＞ gaug, _nŏctem_ ＞ nuech. Such words were very often written in the plural with _-gz_, which was pronounced either ts or tš. The pronunciation ts is attested by such rhymes as _malfagz_: _alumenatz_.