| DNA virus | http://purl.obolibrary.org/obo/MAT_0000195 | DNA virus | |
| dorsal | http://purl.obolibrary.org/obo/MAT_0000487 | dorsal | |
| dorsal aorta | http://purl.obolibrary.org/obo/MAT_0000035 | aorta | |
| dorsal root ganglion | http://purl.obolibrary.org/obo/MAT_0000162 | dorsal root ganglion | |
| Drosophila development | http://purl.obolibrary.org/obo/MAT_0000431 | Drosophila development | |
| Drosophila (FBbt) | http://purl.obolibrary.org/obo/MAT_0000380 | Drosophila (FBbt) | |
| ductus deferens | http://purl.obolibrary.org/obo/MAT_0000129 | ductus deferens | |
| duodenum | http://purl.obolibrary.org/obo/MAT_0000044 | duodenum | |
| ear | http://purl.obolibrary.org/obo/MAT_0000138 | ear | |
| ear | http://purl.obolibrary.org/obo/MAT_0000233 | inflorescence | |
| ear | http://purl.obolibrary.org/obo/MAT_0000317 | female inflorescence | |
| early culminant | http://purl.obolibrary.org/obo/MAT_0000323 | early culminant | |
| early tissues | http://purl.obolibrary.org/obo/MAT_0000304 | early tissues | |
| ectoderm | http://purl.obolibrary.org/obo/MAT_0000173 | ectoderm | |
| ectoderm | http://purl.obolibrary.org/obo/MAT_0000155 | ectoderm | |
| egg | http://purl.obolibrary.org/obo/MAT_0000213 | egg | |
| egg - unfertilized | http://purl.obolibrary.org/obo/MAT_0000124 | egg - unfertilized | |
| ejaculatory duct | http://purl.obolibrary.org/obo/MAT_0000170 | ejaculatory duct | |
| embryo | http://purl.obolibrary.org/obo/MAT_0000226 | embryo | |
| embryo development stages | http://purl.obolibrary.org/obo/MAT_0000407 | embryo development stages | |
| embryo late (growth) stage | http://purl.obolibrary.org/obo/MAT_0000399 | embryo late (growth) stage | |
| embryo mid-stage | http://purl.obolibrary.org/obo/MAT_0000398 | embryo mid-stage | |
| embryonic structure | http://purl.obolibrary.org/obo/MAT_0000019 | developmental tissue - animal | |
| endocardium | http://purl.obolibrary.org/obo/MAT_0000455 | endocardium | |
| endocrine system | http://purl.obolibrary.org/obo/MAT_0000021 | gland | |
| endoderm | http://purl.obolibrary.org/obo/MAT_0000175 | endoderm | |
| endometrium | http://purl.obolibrary.org/obo/MAT_0000319 | endometrium | |
| endometrium | http://purl.obolibrary.org/obo/MAT_0000290 | decidua | |
| endosperm | http://purl.obolibrary.org/obo/MAT_0000227 | endosperm | |
| enteric nervous system | http://purl.obolibrary.org/obo/MAT_0000102 | PNS - enteric | |