atropine n.

one of the Fates, the one who holds the shears and determines the manner of a person's death and cuts the thread, from Greek, literally "inflexible, unchangeable;" etymologically "not to be turned away," from a- "not" (see a- (3)) + stem of trepein "to turn" (from PIE root *trep- "to turn"). The related form atropa was the Greek name for deadly nightshade.

word-forming element in chemistry, often interchangeable with -in (2), though modern use distinguishes them; early 19c., from French -ine, the suffix commonly used to form words for derived substances, hence its extended use in chemistry. It was applied unsystematically at first (as in aniline), but now has more restricted use.

The French suffix is from Latin -ina, fem. form of -inus, suffix used to form adjectives from nouns, and thus is identical with -ine (1).

Proto-Indo-European root meaning "to turn."

It forms all or part of: apotropaic; atropine; Atropos; contrive; entropy; heliotrope; isotropic; psychotropic; retrieve; trope; -trope; trophy; tropic; tropical; tropism; troposphere; troubadour; zoetrope.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit trapate "is ashamed, confused," properly "turns away in shame;" Greek trepein "to turn," tropos "a turn, direction, course," trope "a turning;" Latin trepit "he turns."