It was explained in Mic Looby's regular column. He said the word comes from the Latin for 'delay', because 'according to one legend, a few affixed remora can slow a ship's progress'.
Online Etymology Dictionary says: "sucking fish", 1567, from L. remora, lit. "delay, hindrance," from re- "back" + mora "delay"...Pliny writes that Antony's galley was delayed by one at the Battle of Actium.
I wondered how large they are, that they could slow a ship, so I had a look at a video clip of one attaching itself to a diver who was waiting out a decompression stop on the way up from a dive, and it only seemed as long as his forearm.
Dive The World, where this video was posted, says:
In ancient times, the remora was believed to stop a ship from sailing. In Latin remora means "delay", while the genus name Echeneis comes from Greek echein ("to hold") and naus ("a ship"). Particularly notable is the account of Pliny the Younger, in which the remora is blamed for the defeat of Mark http://www.blogger.com/img/blank.gifAntony at the Battle of Actium and (indirectly) for the death of Caligula.Good on you, little (or not so little) remora, I say. Caligula was no loss, from what I gather.
Here's a fascinating essay with interesting quotes from Pliny. It seems that "Upon its being shown to the emperor [Caligula], he strongly expressed his indignation that such an obstacle as this should have impeded his progress, and have rendered powerless the hearty endeavours of some four hundred men. One thing, too, it is well known, more particularly surprised him, how it was possible that the fish, while adhering to the ship, should arrest its progress, and yet should have no such power when brought on board" (Id.). Thus, Pliny points out, "did an insignificant fish give presage of great events.
Encarta says they grow to about 90 centimetres long, so I suppose if you were rowing around in a galley, a few remoras on the hull might slow you down.
Then I got to wondering about the word moratorium. Back to the Online Etymology Dictionary:
1875, originally a legal term for "authorization to a debtor to postpone payment," from neut. of L.L. moratorius "tending to delay," from L. morari "to delay," from mora "pause, delay," originally "standing there thinking." The word didn't come out of italics until 1914. General sense of "a postponement, deliberate temporary suspension" is first recorded 1932.Well, enough of standing here thinking... I'd better stop.