| Word | Definitions | Synonyms |
|---|---|---|
| pernicious | (adjective) working or spreading in a hidden and usually injurious way | Synonyms: insidious, subtle |
| (adjective) exceedingly harmful | Synonyms: baneful, deadly, pestilent | |
| pernickety | (adjective) characterized by excessive precision and attention to trivial details | Synonyms: persnickety |