(of an internal-combustion engine) having the cylinders ranged side by side in one or more rows along the crankshaft.
Origin of in-line
First recorded in 1925–30
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
denoting a linked sequence of manufacturing processes
denoting an internal-combustion engine having its cylinders arranged in a line
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012