Portato
Sustained, between legato and staccato.
What it means
Portato means “carried” and designates an articulation between binding and separation: the notes are sustained fully, but each receives its own, soft beginning. They hang together as in one line and are nonetheless individually perceptible.
Mezzo staccato is used with the same meaning; for string players the manner of playing corresponds to louré. The designations overlap, and their delimitation is handled differently in the literature.
Portato is to be distinguished from portamento, which, despite the similar name, means something quite different, namely gliding between two pitches. Portato differs from non legato through its more sustained character: there a small gap arises, here the connection remains and only the attack organizes.
In the notation
The manner of playing is notated by short strokes under a slur, more rarely by dots under a slur. Strokes call for the softer, dots the somewhat more distinct separation; not all editions distinguish this. The slur here means belonging together, not binding. Occasionally the word additionally stands there.
Musical use
The manner of playing serves to organize a melody without giving up its line. It stands in sustained movements, with note repetitions that would disappear in pure legato, and in accompanying figures that are to carry without merging. In vocal music it is used when syllables are to be set off but not detached — for instance with text repetitions on the same note.
Portato is notated with dots and a slur or with strokes. Every note is slightly accented and held, but separated. It lies between legato and staccato and sounds speech-like.
Performance practice
Hold the notes almost fully and produce the organization in the attack, not through shortening. With winds a soft tonguing helps, with string players a yielding in the bow arm without lifting, on the piano an attack from the weight with the arm held. Take care that the phrase keeps a direction, so that the organization does not tip into uniformity. And read carefully whether strokes or dots stand there.