| Abbreviation | Meaning | Category |
| R | Recueil des travaus chimiques des Pays-Bas | Periodika |
| R phrase (R-Satz) | risk phrase according to ChemG and GefStoffV (Federal Republic of Germany) | Andere |
| R. A. L. | Atti della Reale Accademia dei Lincei (Rendiconti) | Periodika |
| R. H. | relative humidity | Andere |
| R.D.K. | Roth, Daunderer und Kormann (Hrsg.), Giftpflanzen, Pflanzengifte | Andere |
| racem. | racemisch | Andere |
| rd. | rund | Andere |
| Red. | Reduktion | Andere |
| red. | reduziert | Andere |
| ref. | refer, reference | Andere |
| RERO | Réseau Romand, Verbund der Bibliotheken in der Westschweiz | Andere |
| resp. | respectively | Andere |
| RID | règlement international concernant le transport des marchandises dangereuses par chemin de fer (international convention concerning the transportation of dangerous goods by rail) | Periodika |
| RIS | The Ring Index, 2. Aufl. 1960, Supplement | Andere |
| RNA | ribonucleic acid | Substanz |
| ROSDAL | Representation of Structure Diagram Arranged Linearly | Andere |
| Rp | verschreibungspflichtig | Andere |
| rpm | revolutions per minute | Andere |
| RRI | The Ring Index 2.Aufl.1960 | Andere |
| RSS | RDF Site Summary
Rich Site Summary
Really Simple Syndication | Andere |
| RTECS | Registry of Toxic Effects of Chemical Substances, edited by the National Insitute of Occupational Safety and Health (United States) | Periodika |
