Origin and meaning of "along the lines of"

Solution 1:

The phrase means:

similar in type

• I can't remember exactly what words he used but it was something along those lines.

• I was thinking of doing a dinner party along the lines of that meal I cooked for Annie and Dave.

There is some discussion of its origins here, noting:

Probably from the meaning of "line" defined as sense #15b in the Oxford Engl. Dict.:

"fig. Plan of construction, of action, or procedure: now chiefly in phr. 'on (such and such) lines.'"

"In all very uncultivated countries . . . there are but obscure lines of any form of government" .

"He had reorganized the constitution on the most strictly conservative lines".

To say that "The plot was something along the lines of a murder and a police man" means that the plot line of the novel was something similar to a murder with a policeman. Or, if you're designing a sculpture and have an idea in mind, you can sketch it out and say you want something along those lines--that is, you want "something like this".

Solution 2:

I'm a sailor. I believe that this has a nautical origin, like many phrases. Along the lines refers to two things on a boat, and goes back centuries. One common use waas along the lines of the keel, referring to the midline on a boat. Similarly, lines of navigation were and are critical in successfully making passages, so along the lines also referred to the compass direction in which a boat was travelling, and the continuation of travel along those lines...