Diminutives of masculine words ending -a

Question

Following this question: ¿Cuál es el diminutivo de mano, foto, moto, etc.?, and the quote from the DPD therein:

Lo habitual en la formación de los diminutivos de nombres que acaban en -a o en -o es que el sufijo conserve la misma vocal final del sustantivo, independientemente de cuál sea el género gramatical de este: ... el mapa > el mapita

it seems the common method is to maintain the word's terminal vowel, independent of its gender (with the exception of mano).

But this doesn't seem to be the case for the most common example that comes to mind:

papá > papacito, papaíto

Is the RAE's description out of sync with common practise, or is papá (or words referring to male persons in general) an exceptional case, like mano?

Answer 1

I would say papá is not an exception but a special case. The RAE's description refers to nouns ending in unstressed -a or -o, although it doesn't specifically say so. These endings are by far the most common among nouns, being the ones associated with feminine and masculine gender respectively.

Nouns ending in anything but these two unstressed vowels tend to form their diminutives by adding -c- before the usual suffix (-cito, -cita or -cico, -cica or -cillo, -cilla, etc.), using the last vowel to show the gender of the base noun. Therefore papá > papacito corresponds to cajón > cajoncito or puré > purecito.

If anything, papá is exceptional because it admits not only papacito, but also papaíto and even papito (the last one being truly anomalous).