Troncamento (cutoff), like elision , involves the final vowel dropping out. However, it occurs when the next word begins with a consonant and the last vowel in the word is preceded by m, n, l, r:

tal cosa, cuor d'oro, signor professore, bel palazzo, color rosa.

In the case of troncamento, the words santo (san), bello (bel), grande (gran), frate (fra) change their forms more.

The infinitives particularly often submit to troncamento: aver paura instead of avere paura.