| root motive(expression, reason, importance, significance) |
| root source(expression, reason, importance, significance) |
| shaping factor(expression, reason, importance, significance) |
| top priority(expression, reason, importance, significance) |
| turning point(expression, reason, importance, significance) |
| underlying cause(expression, reason, importance, significance) |
| upstream cause(expression, reason, importance, significance) |
| babyhood(noun, beginning, origin, birth, dawn) |
| beginning(noun, origin, birth, dawn, conception) |
| birthplace(noun, beginning, origin, birth, dawn) |
| fount(noun, beginning, origin, birth, dawn) |
| fountain(noun, beginning, origin, birth, dawn) |
| fountainhead(noun, beginning, origin, birth, dawn) |
| infancy(noun, beginning, origin, birth, dawn) |
| nativity(noun, beginning, origin, birth, dawn) |
| nursery(noun, beginning, origin, birth, dawn) |
| origin(noun, beginning, birth, dawn, conception) |
| source(noun, beginning, origin, birth, dawn) |
| spring(noun, beginning, origin, birth, dawn) |
| wellspring(noun, beginning, origin, birth, dawn) |