Being what was wanted or needed. used to greet someone in polite or friendly way. Friendly greeting to someone who has arrived. To greet someone who has just arrived.

(Being or living) under the surface of the earth. beneath surface of ground. group or movement organized secretly to work against existing regime.

causing great enthusiasm and eagerness. To cause a reaction; make active.

relating to or produced by volcano or volcanoes.

Best liked or most enjoyed. A thing that someone likes best or enjoys most.

What you ask about; issue. To ask for or try to get information.

person who is studying or has expert knowledge of one or more of natural or physical sciences. People who are trained in a science.

fossil reptile of Mesozoic era. Reptile that lived millions of years ago.

person with whom one spends time. People who keep you company, goes out with you. accompany.

Relating to the period before written history.

mountain or hill from which lava, rock fragments, hot vapour, and gas are erupted.

Complex; difficult to understand. undefined.

Way in which two or more things are connected.

Of the top layer; not deep or meaningful. Outside or upper layer of something. To come to the top of something; emerge.

To move closer on all sides of something.