Sentence:  Gnawed within and scorched without, with the <WSD>infixed</WSD>, unrelenting fangs of some incurable idea; such an one, could he be found, would seem the very man to dart his iron and lift his lance against the most appalling of all brutes. 
Meaning of the word marked with <WSD> tags:  To set; to fasten or fix by piercing or thrusting in.