When a word or word string (usually a verb or an adjective, or part of a verb or adjective phrase) serves grammatically in more than one subsequent colon; often defined as the deletion or omission of that word in subsequent cola.
Example
The crumpled, paperwhite residents sat in rows. What could be making death take so long? Some lookedmorefrightened than bored, some [looked]morebored than frightened. (St. Aubyn, 2015: 496)
St. Aubyn, Edward. (2015 [2012]). The Patrick Melrose Novels. Picador.