A thicket is a dense group of bushes or trees. Unlike a hedge, which is a series of bushes that are trimmed in order to create a boundary, a thicket usually occurs naturally and is generally not shaped by human beings.
Ex: Many cardinals hide in thickets so that they're less vulnerable to predators, but if you're lucky you might be able to see one singing from an exposed tree branch.
Ex: As we were hiking, the path seemed to split into two and there were no signs to tell us which way to go. We headed left, but after half an hour of walking the path ended in a thicket so dense that we had to turn around.
Thicket can also be used in a metaphorical sense to refer to anything that seems dense or impenetrable.
Ex: In order to get his work to approve his sabbatical, Roger had to get through a thicket of paperwork. It took him weeks to submit all the required forms, but eventually he achieved it.
Ex: After the defendant was declared not guilty, he exited the courtroom to find a thicket of reporters. Even if the jury thought him innocent, public opinion still considered him guilty.
Woodland refers to any area of land that is covered by trees or other woody vegetation.
Ex: The wild boar's habitat has been greatly diminished since humans have cut down woodlands to make room for new towns.
Ex: We must leave early in the morning if we plan on hiking all the way to the next town; we don't want to be caught in the woodland after dark because we might get lost.
Often people will say woods instead of woodland when talking about forests or other areas covered by trees. The expression not be out of the woods yet means that a situation is still difficult even though things have improved.
Ex: The city has an excellent system of parks that surrounds the urban area. If you'd like to go hiking through the woods, you don't have to drive more than fifteen minutes from the city centre.
Ex: Sales at Donna's restaurant had improved over the summer, but she knew that she wasn't out of the woods yet. She still hadn't made enough of a profit to pay off all the debts, and she knew that she would have fewer customers if the weather got cold very quickly.