An assembly line results when single letters are placed in front of and at the rear of a four-letter word to produce a six-letter word. To illustrate, if and "S" and a "T" were positioned in the front and the rear of EXPO, respectively, a SEXPOT would emerge.
"Assembly Lines -1,"
Word Ways: Vol. 49
, Article 10.
Available at: http://digitalcommons.butler.edu/wordways/vol49/iss2/10