Inspissate is a verb that means to thicken or congeal.

The Latin word spissus (SPEE soos) means ‘think’ or ‘dense.’ Inspissate has been with English since the early 17th century and has maintained the same meaning. Here’s an example:

It was fun to make maple syrup, but I feel we needed to inspissate it a little. Personally, I’ve always liked my syrup as thick as possible.