| ISOTONE | One of a related set of atoms, or with a letter added to the end, a brand of gloves |
| ARENA | Venue that's 26-Down with a letter added |
| SPIREA | Hope to keep to the end a garden shrub (6) |
| ISOTONER | Brand of gloves and slippers |
| SUITE | Related set of computer programs |
| NOSTRIL | Feature composed on list with last letter added (7) |
| SUFFIX | Letters added to the end of a word to form a derivative (6) |
| RANDR | Vacation, briefly ... or the letters added to the starred answers |
| SYSTEM | Nervous, respiratory, reproductive, cardiovascular ... general word for any of the functionally related sets of organs in the human body (6) |
| FORK | What the letters added to the four "stirred" words in this puzzle spell |
| FLAGSHIP | Chief one of a related group (of products, shops etc) |
| ANTIPASTO | Course requires a set of books - one pops related set back |
| TWIN | One of a related pair |
| PAIR | A brace of pheasants, couple of lovers, distich of lines, duo of rowers, duet of singers, dyad of gloves, flight of stairs, yoke of oxen or other two of a kind or twinset of equal things (4) |
| RING | Closed chain of atoms; or, any one of the discs consisting of millions of moonlets orbiting Saturn (4) |
| CHAIN | Part of a molecule consisting of two or more atoms or groups bonded together in a linear sequence (5) |
| AVOGADRO | Italian physicist associated with the number of atoms or molecules in one mole (8) |
| CRYSTALS | Repeating threedimensional arrangements of atoms or ions in the form of beryl, garnet, opal ... (8) |
| CUFFS | Ends of sleeves; parts of gloves or gauntlets covering the wrists; or, the inflatable armbands of blood pressure monitors (5) |
| FREERADICAL | An atom or group of atoms containing at least one unpaired electron and existing for a brief period of time before reacting to produce a stable molecule |
