Surnames Pino, Pinardi, Pini, Pina and others
The surnames Pini, Pino, Pin, Pina, Pinalli, Pinella, Pinèlli, Pinèllo, Pinétti, Pinato, Pinàt, Pineschi, Pinésso derive from the hypocoristic Pino, from Giuseppino (Giuseppe) or sometimes from Filippino (Filippo) or Iacopino (from Iacopo).
In the case of Pinardi, present in Lombardy, the suffix -ardi (indicator of belonging) could therefore refer to the descendants of a Pino (hypocoristic Giuseppe) but could also derive from the fusion of the name Pino with the Germanic suffix hart (hard) meaning something like "Giuseppe the strong".
Remember that the hypocoristic is the phonetic modification (usually an abbreviation) of a personal name, they are those affectionate, familiar or euphemistic appellations used to supplant a real name. It is characterized because the words are subjected to a certain deformation, often being apocopes, apheresis or diminutives of the true proper name.