| NESTS | Successively fits inside each other, as measuring cups |
| NESTED | Fitted inside each other (as boxes) |
| NEST | Fit together, as measuring cups |
| NATION | Kind of commercial pact where two countries agree to treat each other as well as any other (4,8,6) |
| FAVOURED | Kind of commercial pact where two countries agree to treat each other as well as any other (4,8,6) |
| MOST | Kind of commercial pact where two countries agree to treat each other as well as any other (4,8,6) |
| NESTOFTABLES | Pieces of furniture fitting inside each other (4,2,6) |
| PARTYPOLITICS | In which comrades attack each other as much as the opposition? (5,8) |
| CLOSESET | Near each other, as the eyes |
| LIVETOGETHER | Reside with each other, as an engaged couple might (1) |
| INTRODUCE | Make known to each other as two strangers |
| ADJOIN | Be next to each other as hotel rooms |
| LINK | Allow access to each other, as two accounts |
| SILOING | Isolating from each other, as company departments |
| RUSSIANDOLL | Any of a set of hollow wooden figures (matryoshki) designed to fit inside each other (734) |
| POD | Group of people who have contact only with each other as in 2020 |
| STACKERS | Crossword constructors (like me) who put long words on top of each other, as in this puzzle |
| FARRELL | Surname of father and son who have faced each other as coach of the Irish rugby team and captain of the English rugby team (7) |
| SHOP | The ___ Around the Corner 1940 film about two co-workers who fall in love through anonymous letters to each other as pen pals |
| BLOODBROTHERS | Men who have sworn to treat each other as close relatives (5,8) |
