sarcomere n.

1570s, sarcasmus, "a biting taunt or gibe, a satirical remark or expression," from Late Latin sarcasmus, from late Greek sarkasmos "a sneer, jest, taunt, mockery," from sarkazein "to speak bitterly, sneer," literally "to strip off the flesh" (like dogs), from sarx (genitive sarkos) "flesh," properly "piece of meat" (see sarco-). The modern form of the English word is from 1610s. "Now usually in a generalized sense: sarcastic language; sarcastic meaning or purpose" [OED]. Also see humor (n.).

The essential thing about sarcasm is its cutting edge ; it therefore is intensely concentrated, lying in a sentence or a phrase ; it is used to scourge the follies or foibles or vices of men, but has little of reformatory purpose. Satire is more elaborate than sarcasm, is not necessarily bitter, and has, presumably, some aim at the reformation of that which is satirized. [Century Dictionary]

Proto-Indo-European root meaning "to get a share of something." 

It forms all or part of: demerit; emeritus; isomer; isomeric; meretricious; merism; meristem; merit; meritorious; mero-; monomer; Moira; polymer; turmeric.

It is the hypothetical source of/evidence for its existence is provided by: Greek meros "part, lot," moira "share, fate," moros "fate, destiny, doom;" Hittite mark "to divide" a sacrifice; Latin merere, meriri "to earn, deserve, acquire, gain."