plural of derma

The ordinal form of the number thirty.

(intransitive) To become foamy, create a foam; to rise with a foamy surface or covered with something resembling foam / (intransitive, figuratively) To take place, arise, erupt, develop.

(pharmacology, also attributive) A substance which a patient experiences as harmful due to a previous negative perception, but which is in fact pharmacologically (medicinally) inactive.