As Webster's definition suggests, universities differ in several ways from colleges; however, his writeup doesn't really capture the modern use of the term.

Many people think of a college as "an institution that grants only bachelors' degrees," but the technical definition is "an institution that bestows degrees in one particular field of study." So a undergraduate liberal-arts institution like Swarthmore is a college--but so is a medical school or a law school or a divinity school. (The latter are usually called "schools," "institutes," or occasionally "faculties," so people will often look at you oddly if you say you're in "graduate college.") Along the same lines, people sometimes think that any institution that grants graduate degrees is a university, but that isn't true either. Thus, some colleges (such as Middlebury) offer MA degrees as well as BAs, and others (such as the Medical College of Wisconsin) offer no undergraduate degrees at all.

In the US, a university is almost always a collection of two or more colleges, one of which is usually a graduate institution. Thus a university may actually contain several colleges.

Exceptions include Dartmouth College, which has medical and business schools, and Rockefeller University, which only offers PhD degrees.