The name penanggalan derives from the word tanggal, meaning "to remove or take off", because its form is that of a floating disembodied woman's head, with its organs and entrails trailing from its neck.
Only active in penanggal form at night, the creature regularly soaks its organs in vinegar to shrink them for easy entry back into her body.
The penanggal thus carries an odor of vinegar wherever she flies, and returns to her body during the daytime, passing as an ordinary woman.
Furthermore, even if the penanggalan is not successful in her attempt to feed, anyone who is brushed by the dripping entrails will suffer painful open sores that won't heal without a bomoh's help.
The most common protection against a penanggal attack is to scatter the thorny leaves of any of the subspecies of a local plant known as mengkuang, which has sharp thorny leaves and would either trap or injure the exposed lungs, stomach and intestines of the penanggal as it flies in search of its prey.
The shards of glass glued to the top of the walls around a house serve the same purpose, in addition to protecting against thieves.
As an extra precaution, the pregnant woman can keep scissors or betel nut cutters under her pillow, as the penanggalan is afraid of these items.
When meeting people, they will usually avoid eye contact and when performing their midwife duties, they may be seen licking their lips, as if relishing the thought of feeding on the pregnant woman's blood when night comes.