Under Suharto it had dwifungsi, the “dual function” of helping to run the country as well as defending it.

Biofilm, the researchers think, could serve a dual function: it could help bacterial colonies grow toward resources as a collective swarm, and it might also help block out competing colonies.

Antarctic and space studies have found that successful leaders typically perform a dual function of divvying up work and trying to ensure the crew remain emotionally stable.