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

not fulfilling or not expected to achieve intended purpose or desired outcome.

used to emphasize basic, fundamental, or intrinsic nature of person or thing.

having obligation to do something, or having control over or care for someone, as part.

develop gradually.

amount or number of material or abstract thing not. Large amounts of some things.

cause, explanation, or justification for action or event. Explanations for why some things occurred or was done. think, understand, and form judgements logically.

To make, or become, something better.

The very small creatures that can cause disease.

endless or apparently endless.

person one has affectionate bond with. People who you like and enjoy being with. add someone to list of friends or contacts on social networking website.

gladly received. used to greet someone in polite or friendly way. instance or manner of greeting someone. To greet someone who has just arrived.

intellectual and practical activity encompassing systematic study of structure and behaviour of physical and natural world.

continuing or valid to final destination. expressing movement into one side and out of other side of opening etc.. moving in one side and out of other side of.