What is the equivalent for school principal (including either primary school, guidance school or high school) in AmE? Is it usable for all of these grades? What about the words 'headmaster' and 'headmistress'? Note: I am only looking for AE terms.
Indeed it is, in many American dictionaries, the principal noun definition of principal. For example, AHD:
1a. One who holds a position of presiding rank, especially the head of an elementary school, middle school, or high school.
MW uses the broader sense in its full definition, but opens the summary definition with
the person in charge of a public school
Principal as both a title and occupation is almost universal in traditional K-12 state schools (i.e. public school), and no matter the official title of the official, this is the term by which the position will commonly be known. The title is not at all common in American postsecondary education.
There is considerable variation under other public and private educational models (e.g. charter schools, Catholic and other parochial schools, independent schools), and the principal may be known by a variety of other titles.
More than a few such schools adopted British terminology, regardless of whether the school itself follows any part of the British educational model; titles like headmaster / headmistress and head of school are uncommon but not unusual. But these are not interchangeable with principal, due to their connotations; an American is likely to assume a school with a headmaster is an expensive private school, possibly in New England and probably a boarding school.
In contrast, head teacher, which has become conventional in Britain, is relatively rare. A simple COCA search, excluding fiction, turns up the following counts:
- school principal 659
- headmaster 241
- head teacher 51
(It is difficult to search simply on head and on principal, due to their multiple common meanings. But this makes the prevalence of school principal all the more striking, as the other terms are far less ambiguous).