issimo

Is suo is not correct; I should write about "issimo" without confusion.

Is ssi mo? The correct term is issimo. Here is a wiki-style article about issimo.

issimo is an Italian suffix used to form strong intensifiers on adjectives and, in some cases, adverbs. It derives from the Latin suffix -issimus, which expressed a high degree and evolved into the modern Italian -issimo. When attached to a word, -issimo generally conveys the sense of “very” or “extremely.” It is widely productive in Italian and is heard in everyday speech as well as in literature, advertising, and media.

The suffix is typically added to the masculine singular form of adjectives and then agrees for gender and number with the noun. For example, alto becomes altissimo (very tall), grande becomes grandissimo (very large), facile becomes facilissimo (very easy). Feminine forms follow the corresponding feminine stem: alta → altissima, grande → grandissima, facile → facilissima. Some adjective stems undergo familiar phonetic adjustments, such as bello becoming bellissimo and buono becoming buonissimo. For plurals, the ending mirrors the adjective’s plural: altissimi (masc. plural), altissime (fem. plural).

In addition to adjectives, -issimo appears in certain musical terms to indicate very soft or very loud dynamics, such as pianissimo (very soft). This use is well established in musical notation and performance practice.

Usage notes: -issimo is a productive intensifier but does not always correspond to the grammatical superlative indicated by “the most.” It intensifies a quality within a reference and can convey affection, exaggeration, admiration, or emphasis depending on context. It is also customary to avoid overusing -issimo in formal writing where precise degrees are preferred.