Also: slow as molasses in January
Meaning of Idiom ‘Slow as Molasses’
When something (or someone) is as slow as molasses, it is extremely slow; sluggish; not very fast at all.
Usage Notes
This idiom can be used as an adjective or adverb:
Adjective: He is as slow as molasses.
Adverb: He moves as slow as molasses.
As slow as molasses in January is an emphasized variation, based on the fact that molasses, which is thick and viscous and always runs slowly, runs even more slowly when cold.

Sentence Examples
“This computer is as slow as molasses.”
“I had to switch to a new browser. The old one was as slow as molasses.”
“Sorry I’m late. My cab driver drove as slow as molasses.”
“I can’t work with him. It takes him forever to get anything done. He moves as slow as molasses.”

Origin
Used since at least the latter half of the 1800s.
This idiom alludes to how slowly molasses, which is thick and viscous runs or flows.


