- Note: the below discussion was moved from the Wiktionary:Tea room.
The compound word entry includes school bus as a case of compound word. Is that correct? And is school bus a word? (I'd think it is not a word but a multi-word term.) Per the definition from compound in the context of linguistics, school bus is not a compound, as it is not a lexeme.
W:English compound lists "distance learning" as an example of what it calls open or spaced form of a compound word. It classifies the forms as (a) solid or closed, (b) hyphenated, (c) open or spaced. Strange.