I'm trying to learn Italian and I've seen short forms like 'amor' and 'ancor' mainly in songs. Are they used solely to shorten the number of syllables in a verse in music and can more words be shortened in this way?
Are they used solely to shorten the number of syllables? Yes and no.
If you have the opportunity to read poems or writings from the XIII-XIV century written by Italian authors like Dante or Petrarca, you will see tons of truncated words; an example can be the famous quotation from the Divina Commedia:
"Amor, ch'a nullo amato amar perdona"
Here, words truncation leads to two advantaging factors:
- The verse is a hendecasyllable; otherwise, it wouldn't have been and it would have contrasted with the structure of the entire Commedia.
- The flow of words sounds better. This is an important thing, especially in the Italian language: many devices, like this one, are used to have a beautiful sound, when read.
Can more words be shortened in this way? Of course.
There are plenty of words that can be shortened. Nowadays, they are ruled by the modern Italian grammar rules, but in the past (like the times I was speaking about previously) poemwriters tended to shorten or transform words to have them fitting their writings.