Terms appearing in headings or subheadings should not be looked up on the headings, but can be looked up if that appear outside heading tasks.
Excluding terms in h1 - h5 from being looked up would be helpful.
Justification
Any common terms including acronyms that are used in part of a heading, especially a subheading, cause a messy and unhelpful layout - these are especially common as the last or first word in a heading. Excluding these, or excluding certain tags from lookup would be helpful.
Example
On the helminthic therapy wiki, *Necator americanus and *larvae* are both looked up within the subheading The homeopathic remedy, “Necator americanus L3 larvae".