Sentence:  For me Saturday was a bright red color, just as the other days of the week were chromatically coded. ... This wasn't the true <WSD>synæsthesia</WSD> which is such a fascinating mystical hint, a loose thread in the fabric of perception left a-dangle, an unravelling which suggests that we could dissolve all our unreal categories. 
Meaning of the word marked with <WSD> tags:  A neurological or psychological phenomenon whereby a particular sensory stimulus triggers a second kind of sensation. (from late 19th c.)