Parity vs Parity bit vs Parity sum Assume that $B_b$ denotes the finite set of bitstrings of length $b$, if we are given its subset $A = \{e_i\}, i \in \{0,... n\}$, such that $e_i \in B_b$, what is "the parity sum of As bitstrings" ($parity_A$)?

Is it a single bit $parity_A = parity(concat(parity(e_1), parity(e_2), ..., parity(e_n)))$?

Or is it a bitstring $parity_A = concat(parity(e_1), parity(e_2), ..., parity(e_n))$?

Or is it something else?
I don't think the term has a clear standard accepted meaning, so if you are reading it somewhere, you'll either have to infer from context or hope they defined the term.  But as a general guideline, I would guess your former choice is much more likely than your second choice; I think it's much more likely to be a single bit than a bitstring.

If you are thinking of using that term in your own writing, I encourage you to define that term before using it.