late 14c., "involving faith in supernatural powers or magic; characteristic of pagan religion or false religion," from Anglo-French supersticius, Old French supersticios, or directly from Latin superstitiosus "prophetic; full of dread of the supernatural,"* from superstitio "prophecy, soothsaying, excessive fear of the gods". See
from super "above" (see super-) + stare "to stand," from PIE root *sta- "to stand" (see stet). There are many theories to explain the Latin sense development, but none has yet been generally accepted. Originally in English especially of religion; sense of "unreasonable notion" is from 1794.
As for the hyphen use:
While the formation of the Latin word is clear, from the verb super-stare, "to stand over, stand upon; survive", its original intended sense is less clear. It can be interpreted as "‘standing over a thing in amazement or awe",but other possibilities have been suggested, e.g. the sense of excess, i.e. over scrupulousness or over-ceremoniousness in the performing of religious rites, or else the survival of old, irrational religious habits.
I have never had any doubt, thanks to a sound classical education, that SUPERSTITION - a word found in many modern languages - derives from an amalgam of SUPER (preposition usually governing the accusative case meaning ABOVE) and STARE (an irregular but perfectly normal 1st conjugation verb, in the present tense, meaning TO STAND or TO BE (in a non- intrinsic sense q.v. STARE in Italian or ESTAR in Spanish as opposed to ESSE/ESSERE/SER).
Thus the modern semantic concept is of a thing which claims to possess or is treated as possessing, qualities "additional to what it most clearly or visibly possesses" and so can be dismissed by the illuminati as ILLOGICAL.