Summary: In the Abhidhamma, rūpa is the material side of conditioned experience. The Dhammasaṅgaṇī defines "all matter" as the four great elements together with matter derived from them, while the Vibhaṅga frames the same field under the rūpakkhandha (Dhs 596; Vibh 1).
Canonical locus
The canonical definition in the Dhammasaṅgaṇī and the aggregate framing in the Vibhaṅga give the two main anchors for this page. (Dhs 596; Vibh 1)
Dhs 596 (ds2.2.2:1.1–1.3)
Tattha katamaṁ sabbaṁ rūpaṁ? Cattāro ca mahābhūtā, catunnañca mahābhūtānaṁ upādāya rūpaṁ — idaṁ vuccati sabbaṁ rūpaṁ.
Vibh 1 (vb1:3.1–3.3)
Tattha katamo rūpakkhandho? Yaṁ kiñci rūpaṁ atītānāgatapaccuppannaṁ ... tadekajjhaṁ abhisaññūhitvā abhisaṅkhipitvā — ayaṁ vuccati rūpakkhandho.
Analysis
Abhidhamma analysis treats rūpa as a distinct but conditioned domain, defined structurally and then classified in increasingly fine ways. (Dhs 596; Vibh 1)
The canonical definition is structural
The Abhidhamma does not define rūpa by ordinary appearance alone. It defines it structurally as the four great elements (mahābhūta) and the forms dependent on them. (Dhs 596)
Rūpa is conditioned and analyzable
The Dhammasaṅgaṇī immediately classifies matter as conditioned (saṅkhata), mundane (lokiya), non-mental (acetasika), and consciousness-disjoined (cittavippayutta). That is, matter belongs fully inside conditioned reality, but it is not itself a mental event. (Dhs 596)
Aggregate and dhamma-analysis meet here
The Vibhaṅga approaches the same domain from the five-aggregate framework, while the Dhammasaṅgaṇī handles it through finer dhamma-analysis. Together they show that Abhidhamma rūpa is not separate from the sutta framework, but a tighter analysis of one of the aggregates. (Vibh 1; Dhs 596)
Textual notes
- English "form" is traditional, but in Abhidhamma contexts "matter" or "material phenomenon" is often clearer because the term covers the whole material side of experience, not shape alone.
- The familiar later count of twenty-eight material phenomena is a standard Theravāda analytical presentation built on this canonical definition. This page anchors first in the canonical definition itself. (Dhs 596)