Where does the term "boost" come from for rotation-free transformations? I had never seen rotation free transformations called "boosts" (I think I have it right) before reading some questions here. I'm too old perhaps. I have not found the etymology after some searching, though it sounds like something V.I. Arnold would think up, or jargon from inertial navigation. Anyone know where/how it started or was popularized? (If it is in MTW or Ohanian (old edition) or Weinberg, I promise I'll facepalm)
 A: Not necessarily the original source of the term, but the earliest use I can find, occurs in Brandeis University Summer Institute in Theoretical Physics, 1964 Vol. 1: Lectures on General Relativity, where on p. 208:

If we use the term boost for a Lorentz transformation from one frame to another parallel to it but with a uniform velocity relative to it, then we can analyze the motion according to the type of transformation as follows: ...

No particular reason as far as etymology is given, though one can guess some plausible analogies. Notably, one can find easily find some uses within a few years after the above on Google Books, including one briefly gives some synonyms for it,

All of these examples of so-called "pure Lorentz transformations" or "accelerations" or "boosts" (perhaps boost is preferable, as it does not invite misunderstandings) i.e., transformations of the type...

as well as a reason to prefer "boost" (besides simply being less of a mouthful, I suppose).
A: In Gravitation, Misner, Thorne and Wheeler first use the term boost in box 2.4 starting on page 67. They don't make a fuss of defining the term, so I assume it must have been in common use at the time of publication (1970).
