A 'bachelor' is an unmarried man. There are a few types of certificates for education. I'll explain them in order of value: Diploma: American students get this for graduating from high school. Associate's Degree: This comes from a 2-year study program after high school, usually from a Community College. Bachelor's Degree: This comes from a traditional 4-year university. While a student is in a university studying to get a Bachelor's Degree, they are called "undergraduates" or "undergrads". Master's Degree: This comes after a student has a Bachelor's Degree. They can move on to a more specialized area of the university for 2 more years (usually). While a student is studying to get a Master's Degree, they are called "graduates" or "grad students". Doctorate: This is the highest level of education a person can achieve. Doctorate programs differ a lot in what they require, but a Master's-holding student will have to publish work in their field of study to obtain a Doctorate. Even though we call them "Doctors" in hospitals, they have an M.D., which is different than a standard Doctorate. There are also degrees from Law School, which is also different than the more well-known degrees I mentioned above.

An undergraduate is a person who is studying for a bachelor's degree (please note the apostrophe and the s). He has not obtained the degree yet. He is pursuing his undergraduate studies. He is at university on a course that leads to a bachelor's degree. I hope the above sentences are not only an explanation but also examples of usage for you.

In the United States, the word "bachelor" means an unmarried man. The usual degree awarded for four years of university education is a "bachelor's degree," sometimes "baccalaureate," but someone who holds such a degree is NEVER called "a bachelor," never. The usual term is "a graduate." Universities are quite independent from each other, and public universities vary from state to state. There are vague cultural patterns but no precise rules. In fact, there is no precise definition of "a university." After spending four years at a university and receiving a bachelor's degree, a common pattern is to continue on to get a master's degree, often in two years. However, someone with a master's degree is NEVER called "a master." There is no short name for it. People simply say "I have my master's." Another common pattern, after receiving the bachelor's degree, is to continue on to get a doctorate, often a Ph. D. This usually takes a minimum of four years, but can take much longer. A doctorate requires original academic work and means that one has joined the community of scholars. A master's degree may or may not be received as part of the progress toward a doctorate. Someone with a doctorate may be addressed with the honorific "Dr." Someone with a doctorate is almost never referred to as "a doctor" UNLESS they have a medical degree, or something related--a dental degree, an optometry degree, a veterinary degree, an osteopathy degree, etc. Thus, we might introduce Albert Einstein as "Dr. Einstein," but he is not "a doctor," he is "a Ph. D."