Other forms: fastidiousnesses
Fastidiousness is a quality of caring a lot about how accurate or tidy things are. Being a great proofreader requires fastidiousness.
Taken too far, fastidiousness can mean you worry and obsess over every little detail — or every tiny crumb or stain on your shirt. But having a degree of fastidiousness means you pay attention to details and do your work with great care. The source of this word is the Latin fastidiosus, "exacting," but also "squeamish," from fastidium, "squeamishness, dislike, or aversion."