In textual criticism, a colon is a line consisting of a single clause.
In the following case of Hebrew poetry, the bolded text represents a bicolon, with a backslash separating individual cola.
For example, both verses in Quran 2:3–4 can be considered a tricolon:[5]3 who believe in the Hidden / and perform prayer / and of that which We have provided for them do spend, / 4 and who believe in what was sent down to you / and what was sent down before you / and in the world to come place their trust.
The average number of syllables per colon, counted across nearly one-hundred psalms, is typically eight, and sometimes seven or nine.
Nine is the "ceiling" because there are no psalms which have an average number of syllables per colon above that, but twelve have exactly nine.