A lot vs. Alot: 9 Grammatical Pitfalls
1822, from re- "again" + hash (v.). Related: Rehashed; rehashing.
1849, from rehash (v.); "old material worked up anew," usually of literary productions.
: a rehash of stale political charges
To review; discuss again; repeat; recap: the things they had hashed and rehashed for many a frugal conversational meal
[1880+; called vulgar in the dated source]