πικρός (pikróspik-ros'adjectivebitter)
[Grk] πικρός LN: 79.41, 88.170 GK: G4395 Hebrew: מַר, מָרַר, רֹאשׁ
Derivation: perhaps from πήγνυμι (through the idea of piercing);
Strong's: sharp (pungent), i.e. acrid (literally or figuratively)
KJV: --bitter.
See: πήγνυμι