| Answer | Crossword Clue |
|---|---|
| CLANS | Sometimes warring groups |
| SEXES | Warring factions, sometimes |
| SECTS | Splinter groups, sometimes |
| porphyrins | Any of a class of pigments (including heme and chlorophyll) whose molecules contain a flat ring of four linked heterocyclic groups, sometimes with a central metal atom |
| porphyrin | Any of a class of pigments (including heme and chlorophyll) whose molecules contain a flat ring of four linked heterocyclic groups, sometimes with a central metal atom |
