A phrasal template is a phrase-long collocation that contains one or several empty slots which may be filled by words to produce individual phrases. Often there are some restrictions on the grammatic category of the words allowed to fill particular slots. An example is the phrase "common stocks rose <Number> to <Number>", e.g., "common stocks rose 1.72 to 340.36".
Phrasal templates are akin to forms in which blanks are to be filled with data.
A word game that makes use of phrasal templates is Mad Libs.
The notion is used in natural language processing systems and in language generators, such as application-oriented report generators.
The neologism "snowclone" was introduced to refer to a special case of phrasal templates that "clone" popular clichés. For example, a misquotation of Diana Vreeland's "Pink is the navy blue of India" gave rise to the template "[X] is the new black," which in turn evolved into "[Y] is the new [X]" constructions such as "pink is the new red" and Quiet Is the New Loud.
The term "phrasal template" first appeared in a linguistic study of prosody in 1983 but doesn't appear to have come into common use until the late 1990s.