from The American Heritage® Dictionary of the English Language, 4th Edition
- n. The outer layers of tissue of woody roots and stems, consisting of the cork cambium and the tissues produced by it, such as cork.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. The outer layer of plant tissue; the outer bark.
- n. The perisarc; the hard outer layer of hydroids and other marine animals.
from the GNU version of the Collaborative International Dictionary of English
- n. The outer layer of bark.
- n. The hard outer covering of hydroids and other marine animals; the perisarc.
from The Century Dictionary and Cyclopedia
- n. In zoology, epiderm or cuticle forming an investing sheath or tube, as in some tubularian hydromedusans; a kind of hard perisarc or cortical layer of the cœnosarc of certain hydrozoans.
- n. 2. In botany, the continuous layers of cork which cover the stems of many plants after they acquired a certain age.
From peri- + -derm (Wiktionary)