Sinister is the Latin word for left-handed. What evolution of meaning turned left-handed into evil and threatening?
So, if you were left-handed or sinister, you were associated with evil. In time, sinister itself meant evil and threatening. EtymOnline said that sinister attained this meaning in the early 15th century. The OED supports this, writing that the first uses of sinister to mean malicious were:
This goes back to the art of divination the early Romans named avspecium (coined after aves "birds" and specio "I watch" => specious). Bird-watching the Roman way so to speak.
One way auspices would use to guess good and bad omens was to watch which direction some auspicious types of birds like ravens, crows or eagles were flying by. These birds were supposed to play the role of messengers of the gods. Here is a nice study of this type of divination.
This was also practised in Ancient Greece and named οἰωνίζομαι (ornithomancy).
If birds were flying by on your right this was good omen. On the left (sinistra) that was bad omen.
The word sinistre was already a synonym of bad omen in Old French but had lost the meaning of "left" when it was introduced into Middle English.
In Italian though it still has both meanings.
The etymological path, as far as I understand it, is as follows:
1a. Early Ancient Greek σκαιὀς, "left, awkward, ill-omen",
Also consider the following points:
Another curiosity I'd like to mention is that the aforementioned Early Ancient Greek word for left (σκαιὀς, "skaios") and its Latin cognate (scaevus) seem to come from a Proto Indo European root for shadow (same etymology actually as "shadow" itself): (PIE *skeh2-i-uo-, via Pt Italic *skaiwo) which is to compare to several other Indo European languages (various Celtic languages, Greek, Lithuanian, Sanskrit, Avestan) in which right-hand side also means southwards.
There is a lot of evidence suggesting that ancient Indo Europeans and Semites orientated themselves facing eastwards (like old maps do) because this is where the sun rises in the morning.
In the northern hemisphere, when one faces eastwards the sun is always on the right-hand side and one's shadow is thus always on the left-hand side, which explains the relation in some antique words for left with similar words for shadow.
I'm surprised that the answers so far haven't mentioned two factors, neither of them decisive but both relevant.
First, it's not so long ago that left-handed schoolchildren were punished for their 'wilful disobedience' in writing with the wrong hand; this was either because they made the rows of children writing at desks look untidy or because, with fountain pens universal, covering the new words with your hand (as lefties do in left-to-right writing) causes smudges. [Choose your preferred explanation: both can be found in convincing sources].
And mediaeval heraldry used the bar sinister as a mark of illegitimacy. 'Sinister' here meant only 'starting from the left, the unusual side', and the mark was a practical and non-judgmental "document" in pre-literate times. Fathers and legitimate children, however, saw such people as a threat to their position, and thought them unpleasant if not positively sinister.
In the old days, abnormality was considered vile and dangerous. One example is how the music from Middle Ages had only Melody in their music and not Harmony. This was because Christian churches only used one Melody for music. They were very much against unusual things like left-handedness and Magic.
To add to the many other answers, before the introduction of toilet paper, the convention was to eat with the right hand and to clean up after using the toilet with the left. There are many examples of left hands and left-handedness being seen negatively as a result of that.
There is a folk-etymology that "cack-handed" (meaning clumsy or left-handed) refers to this, the dialect word "cack" referring to faeces.
Years ago, an attorney friend w/a history background, told me 'sinister', and, therefore,'sinistralian', etc., came from the Roman legion's concern about fighting alongside a left-hander while in the tortoise formation.
Perhaps not an evolution in or from Latin, but a contribution (in late ancient empire times) to Latin (from remotely ancient, Hebrew times).
suggests an origin in Judaic scripture and teaching, extending back possibly as far as the Patriarchal era. The concept seems to have related to a connection between heart and mind, the left (sinister) heart harboring innate (embued in the womb) evil influence on the mind; the right (dexter)...the opposite.
In the current, less descriptive, more "scientific" era it might be said that such a "manifestation," whether in belief or in actuality, might rest in the connection and dialog between reasoning and feeling (except with up and down orientations reversed) parts of the brain.
To think that such a concept is considered antiquated (or quaint) in current times is not comprehensively refutable:
Lefthandedness, even within a still living (barely) generation, was held (putting it kindly) to be "not so good" and/or "not well-forboding,"--even so bad as to be a visitation of life misfortune--and was sought to be reversed by training, both in homes and in schools. (...ever see a cursive writing chart showing pencil gripped in curl-around orientation?)
Confused handedness is sometimes observed clinically as a trait of some mentally disabled.
While no physiological, genetic, or congenital reason for abberent (left) handedness has yet been discovered--and left-handedness does not run in families--a clear connection between left handedness and trauma/accident/stress during the pre-handedness phase of fetal or infant development has been documented.
And might we ask if calling a person a southpaw (probably most people do not the source of that word) could have any connection to the term whereby things, luck, situations, prospects (etc) are said to "go sinisterly south"? (Please don't pounce. Just a supposition...only for fun.)
...if only Kipling were still around, to give the world a kinder-hearted replacement of that particular S word!
PS: Speaking of wombs and modern observations of early life influence on handedness, it certainly seems as if doctors of long-ago times had things to show us today, for which, in this instance, we had the Romans to thank for passing their words forward in time.
protected by RegDwigнt♦ Apr 20 '14 at 15:52
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