kw + kw ＞ k + kw: quīnque ＞ cīnque ＞ cinc.
l + l ＞ r + l, — + l, d + l: calamĕllum ＞ calamęl caramęl, ✱umbilīcŭlum ＞ emborígol, flēbĭlem ＞ flẹble frẹble fẹble, ŭlulāre ＞ ulular udolar. Perhaps püs = plüs ＜ plūs is to be explained by dissimilation, occurring in such phrases as plus larc, plus lonc.
m + m ＞ n + m: memorāre ＞ membrar nembrar (renembransa).
m + n ＞ m + r: ✱comĭnicāre ＞ comenegar comergar, ✱indomĭnicātum ＞ endomeniat endomergat, mancĭpium ＞ mansip massip marsip, manĭcum ＞ margue, mŏnăchum ＞ mongue morgue.
n + m ＞ r + m: anĭma ＞ anma arma, ✱mĭnimāre ＞ mermar.
n + n ＞ n + r, r + n; ? d + n: canŏnĭcum ＞ canónegue canorgue, venēnum ＞ verin; nec ūnum ＞ negün degün? (cf. Andalusian and Asturian dengun, Catalan dingu, apparently from nec ūnum + nĭngŭlum).
r + r ＞ r + —, — + r, l + r: ✱Bernhardum ＞ Bernart Bernat, marmor ＞ marbre marme, prŏprium ＞ prǫpri prǫpi; dīe Mércūrī (influenced by dīe Vénĕris) ＞ dimęrcres dimęcres, grandem rem ＞ granrẹ ganrẹ, pr(eh)ĕndĕre ＞ prenre penre, prĕsby̆ter ＞ pręstre pęstre; arbĭtrium ＞ albire, ✱Arvĕrnium ＞ Alvęrnhe, peregrīnus ＞ pele(g)rīnus ＞ peleris, pŭrpŭra ＞ pọlpra.
s + s ＞ — + s: ✱spasmāre ＞ (espasme) pasmar (cf. French pâmer), perhaps through confusion of the initial es- with the prefix ex-.
t + t? ＞ — + t: statiōnem? ＞ sazọ (cf. French saison, Spanish sazon).
y + y ＞ y + —: ✱disjejūnāre ＞ ✱disjeunāre ＞ ✱disy’nāre ＞ dis´nar disnar.