Ciel's j. 236c is also cancelable on whiff after landing(unless it was removed, its mostly useless and I haven't tested it in b2 yet). I think it was featured in a video somewhere. There are a lot of moves cancelable on whiff, like non-standard chains(like Ciel's 5cc, 2cc, etc.) as well as standard A attacks. Just to save Chibi a post Hisui's 623b is cancelable into 623c on whiff as well.
We have been getting a tad off topic, so lets refine what we are talking about as: Chaining a move with longer recovery into one with less recovery to make it safer. Most of the time this is done with 5a but it can be done with other normals as well. This will almost always incur a reverse beat, but isn't a requirement. The move(s) can either whiff, be blocked, or hit.
Examples of what is:
(all examples can have anything before it, whether it be a 100 move block string or nothing at all)
2c5a, Using the 5a to shorten the recovery on this string.
2c5b, Same thing, only using a 5b instead of 5a.
2a5b, Same thing, only using the 5b to shorten recovery on the 2a.(obviously no actual in game examples where this would be used, but if it could this would fit the description)
All three can have either move whiff, block, or hit.
Examples of what is not:
2c5a5c, Standard reverse beat chain followed by another move in the chain.
2c5a, 2c, a combo. The 5a(whiffed) is used to shorten the recovery of 2c so you can combo a second one. Shortening recovery for combo purposes isn't included in this(although it could be changed to be included). If the 5a doesn't whiff it is just a standard link combo with some unrelated technical workings.
2c, 5a. This is just a 2c linked into a 5a, no canceling is being done.
2c5a, the 2c is canceled late into a whiff 5a, to the point where 5a's total frames are greater than the remaining frames of the 2c.(IE if 2c will recovery in 5 frames, at which point you cancel into 5a(whiff) which takes 10 frames, you are putting yourself into 5 extra frames of recovery)
2c5ad, The 5a(whiff) cancels the recovery of 2c, which may be one, but the 5a is then canceled into a shield, which while may make it safer against some things, doesn't fit the description. If the shield was done in reaction to something then the 5a is still one.
As for names, whiff canceling is out. Whiffing something has nothing to do with anything, it is just something that could happen. Jab canceling, while I don't like it, is at least somewhat appropriate. Something that focuses on the recovery aspect is what we're looking for, and jabs are typically good with recovery. My original suggestion of reverse beat a's doesn't work with this.