What is the X in X-mas?
"moral misgiving, pang of conscience," late 14c., from Old French scrupule (14c.), from Latin scrupulus "uneasiness, anxiety, pricking of conscience," literally "small sharp stone," diminutive of scrupus "sharp stone or pebble," used figuratively by Cicero for a cause of uneasiness or anxiety, probably from the notion of having a pebble in one's shoe. The word in the more literal Latin sense of "small unit of weight or measurement" is attested in English from late 14c.
"to have or make scruples," 1620s, from scruple (n.). Related: Scrupled; scrupling.
scruple scru·ple (skrōō'pəl)
An uneasy feeling arising from conscience or principle that tends to hinder action.
A unit of apothecary weight that is equal to about 1.3 grams, or 20 grains.
A minute part or amount.
unit of weight in the apothecaries' system, equal to 20 grains, or one-third dram, and equivalent to 1.296 grams. It was sometimes mistakenly assigned to the avoirdupois system. In ancient times, when coinage weights customarily furnished the lower subdivisions of weight systems, the scruple (from Latin scrupulus, "small stone" or "pebble") was a unit of Roman commercial weight as well as a unit of coinage weight. One drachma, the basic Greek silver unit, consisted of three scruples.