There are a few problems students may come across with the word bark. There are several different words written like this, three nouns and two verbs, and there are also several versions of one of the nouns - as well as some derivative words.
- The noun 'a bark', with the associated verb 'to bark', is the sharp explosive noise made by dogs (and other animals such as wolves and hyenas), often repeatedly. Dogs bark mostly as a warning. It may be used figuratively to describe the way some people speak. It has given rise to the colloquial adjective barking, used to mean 'insane', as in "barking mad". The image is of 'uncontrollable', like a rabid dog, or simply of a lunatic making loud, sudden non-human noises.
- The bark of a tree or other woody plant is the hard 'skin' of the trunk, often rough in texture but sometimes smooth. It has given rise to a verb with several meanings :
- Historically, 'to bark' was used to mean 'to tan' (see below);
- 'to bark' a tree is to kill it by stripping a circle of bark (through which the nutrients run) all the way round the trunk, thus effectively starving the tree to death;
- 'to bark' one's shin (sometimes another part of the body) is to graze it painfully by scraping it vertically;
- 'to bark' over a gap is to form a hard skin over it. Human wounds vcan (figuratively) bark over with time; trees can - more literally - bark over a scar where they have been cut.
- Historically, oak-bark was the most important source of tannin, the active agent in the process of 'tanning' leather (making it out of raw skins). Many references to this use of bark occur in older texts.
- At sea, a bark or barque is the name of a type of vessel. What type has changed as seafaring has developed: see further bark - barge - barque.