I look for a verb that conveys gentle slow-motion wriggling.
For example, the octopus tentacle ... further into the sand.
According to the classical dictionaries OEL, OALD, CALD, etc. wriggling conveys with short writhing motions like a worm. I'm looking for a word that does not insinuate writhing.
Words like to drill, to bore, etc. do not fit here, because of the context of the sentence. My real sentence is different but the octopus tentacle conveys the idea of the movement.
My sentence is about a tangible sensation that permeates the body slowly over time, and that sensation has a clear physicalness, it's not an imagination. However, it can't be measured although the effect of it worming through the body should be measurable. (Somewhat similar to measuring the Higgs boson.