Afterhood

Part of speech: noun

Definitions

1. The condition or time of life spent as a younger sibling or junior member of a family
2. The status or experience of being born after one or more other children in a family
3. The period or circumstance of existing as a subsequent child rather than a firstborn

Etymology: "After" comes from Old English "æfter," and "-hood" comes from Old English "hād," meaning "state, condition, or rank." That same suffix appears in "childhood" and "manhood," where it marks a state of being. Joining the two gives a formation meaning roughly "the state or time that follows." Because "afterhood" is rare and built transparently from its parts, it has no separate story of coinage that I can confirm, and I am uncertain of its earliest recorded date. Its meaning is plain from the parts, so the suffix does most of the explaining.