| gate |
| grass roots |
| hatching(noun, beginning) |
| hornbook(opening, addition, establishment, preface, foreword) |
| incunabula |
| induction(start, top, beginning, opening, creation) |
| influx(opening, addition, establishment, introduction, preface) |
| ingress(cause, beginning, opening, addition, establishment) |
| insertion(opening, addition, establishment, introduction, preface) |
| inspiration(cause, influence, source, spring, stream) |
| instauration |
| interpolation(opening, addition, establishment, introduction, preface) |
| intro(start, beginning, opening, addition, establishment) |
| jump-off(noun, beginning, opening, birth, dawn) |
| lead(opening, addition, establishment, introduction, preface) |
| lead-in(noun, start, beginning, opening, addition) |
| leaving(noun, beginning, opening, birth, dawn) |
| line |
| lineage |
| mainspring(cause, source, spring, origin, stream) |