Mereerah , denoting "that which is bitter;" hence the term is applied to the "bile" or "gall" (the fluid secreted by the liver), from its intense bitterness, (Job 16:13; 20:25) it is also used of the "poison" of serpents, (Job 20:14) which the ancients erroneously believed was their gall.
Rosh , generally translated "gall" in the English Bible, is in (Hosea 10:4) rendered "hemlock:" in (32:33) and Job 20:16 rosh denotes the "poison" or "venom" of serpents. From (29:18) and Lame 3:19 compared with Hose 10:4 it is evident that the Hebrew term denotes some bitter and perhaps poisonous plant. Other writers have supposed, and with some reason, from (32:32) that some berry-bearing plant must be intended. Gesenius understands poppies; in which case the gall mingled with the wine offered to our Lord at his crucifixion, and refused by him, would be an anaesthetic, and tend to diminish the sense of suffering. Dr. Richardson, "Ten Lectures on Alcohol," p. 23, thinks these drinks were given to the crucified to diminish the suffering through their intoxicating effects.