Q. I am a consultant in the information systems industry. I am aware that the common utilization of technical tools has widely affected formal English grammar. One of the challenges I face when presenting my analysis to clients is the proper use of compounds. For example, “filesystem,” which I understand from research is not properly one word, but I see elsewhere that “hardware” and “software” are. I believe these latter are compounds simply by the fact of their commonality in day-to-day conversation. Am I simply waiting for the day that “file system” will be part of normal vernacular and blessed by CMOS to be “filesystems”? Can you clear up my confusion?

A. The compound “file system,” regardless of its growing application with computers, is a poor candidate for becoming a single word. Any efficacy in making it a single word in some technical settings is outweighed in everyday prose by the bad fit between the two words. Though it is not an easy matter to predict such things, compounds formed of two separate words must have something going for them if they hope to form an intimate relationship. One thing that helps is analogous antecedents. A perusal of a couple of dictionaries reveals that among compounds in which “file” is the first word, only “filefish” (a relative of the triggerfish) has become one word (though it remains “file-fish” in the OED; such hyphenation is more common in British than American English). By contrast, the preexistence of “hardware” (since the fifteenth century, according to Merriam-Webster) virtually guaranteed one-word status for “software” (which was born, according to M-W, the same year Madonna was). Words also must sound as if they belong together, which is why “website” works so well. Note that Microsoft, to its credit, seems to prefer “file system” in its documentation—even though, for example, specific procedures might invoke and require the syntax FileSystem or filesystem. Finally, a caveat: as our own preference for “copyeditor” has shown (M-W lists “copyedit” [v.] but “copy editor” [n.]), it is not always easy for a specialist community to impose its own usage on the rest of the world.