midrange and midbass aren't the names of speakers, but names given to certain ranges of the audible frequency range
in a 2-way system, a woofer is used to reproduce midbass AND midrange, and a dedicated midrange driver in a 3-way component setup is usually referred to as a squawker, and then we all know and love the tweeter, and then comes the always contraversial supertweeter, which plays from anywhere from 5-20khz up to 30-60khz, for people who have more money than sense, and want to call dogs and squirrels from miles away.