| necessary(adjective, important, significant, original, essential) |
| capital(adjective, essential, fundamental, main) |
| chief(adjective, top, essential, prime, vital) |
| congenital(adjective, essential, basic, absolute, fundamental) |
| inborn(adjective, essential, basic, absolute, fundamental) |
| innate(adjective, essential, basic, absolute, fundamental) |
| material(adjective, essential, basic, absolute, fundamental) |
| substratal(adjective, simple, plain, important, significant) |
| connate(adjective, essential, basic, absolute, fundamental) |
| deep-seated(adjective, original, essential, basic, absolute) |
| inbred(adjective, essential, basic, absolute, fundamental) |
| meat and potatoes(expression, adjective, idiom, simple, plain) |
| nitty-gritty(adjective, original, basic, absolute, fundamental) |
| nub(adjective, original, basic, absolute, fundamental) |
| absolute(adjective, basic, fundamental, central) |
| cold(adjective, basic, absolute, fundamental) |
| complete(adjective, basic, absolute, fundamental) |
| ideal(adjective, basic, absolute, fundamental) |
| name of game(expression, adjective, idiom, absolute) |
| name of the game(expression, adjective, idiom, basic, absolute) |