- Required or necessary as a prior condition.
- Something that is prerequisite, as a course that is required prior to taking an advanced course.
- Previously required; necessary as a condition of something following.
- A condition required beforehand; a preliminary necessity.
- Previously required; necessary as a preliminary to any proposed effect or end.
- Something previously required, or necessary to an end or effect proposed.
- <xref>Required</xref> as a <xref>prior</xref> <xref>condition</xref> of something else; <xref>necessary</xref> or <xref>indispensable</xref>.
- Something that must be gained in order to gain something else
- In education, a course or topic that must be completed before another course or topic can be started. May be <xref>colloquially</xref> referred to as a prereq.
- something that is required in advance
- required as a prior condition or course of study