| MONOMANIA | Obsession with a single subject |
| ONETRACKMIND | Obsession with a single objective (3-5,4) |
| ABONETOPICK | Seaman with a single subject, potassium, as a matter of dispute (1,4,2,4) |
| ONETRACK | Obsessed with a single subject (3-5) |
| MONOGRAPHS | Papers or books concerned with a single subject (10) |
| THING | A slight obsession with a historic assembly (5) |
| MONOGRAPH | Treatise on a single subject, or one aspect of a subject (9) |
| WONK | A nerd focused on a single subject |
| PAMPHLET | A small brochure containing information about a single subject (8) |
| ALEVEL | School examination in a single subject (1,5) |
| BRIAR | A single subject of this week's Miscellany! (5) |
| BLACKBERRY | A single subject of this week's Miscellany! (10) |
| INTENSIVE | Concentrated on a single subject (9) |
| BEEINONESBONNET | Obsession with a buzzing in the ears (3,2,4,6) |
| LOLITA | Vladimir Nabokov's novel about Humbert Humbert's obsession with a young girl (6) |
| THEMED | Goethe Medal has focused on single subject ... (6) |
| ESSAYISTS | Authors who write pieces on single subjects |
| ECONOMICS | Online magazines containing not a single subject (9) |
| DUDISH | A dandy or fop's obsession with fashion, finery and stylish charm; or, the manner of an overly meticulous city slicker, once visiting a ranch or farm (6) |
| MANIAC | Has he a mad obsession with Charlie? |
