I’ve always been interested in etymology or the story behind the origins of words.
I haven’t been as successful finding a good reference book or website though until now.  Check out 
http://www.etymonline.com/ for a new perspective on some old vocabulary.
We, of course, use words all the time but we don’t often know their stories.  Here are a few examples from the website (notice the origin of the world school below; bolded text are my highlights).
daisy (n.) 
Old English 
dægesege, from 
dæges eage “day’s eye,” because the petals open at dawn and close at dusk. (See 
day (n.) + 
eye (n.)). In Medieval Latin it was 
solis oculus “sun’s eye.” As a female proper name said to have been originally a pet form of 
Margaret (q.v.).
 
school (n.1) 
“place of instruction,” Old English 
scol, from Latin 
schola “intermission of work, leisure for learning; learned conversation, debate; lecture; meeting place for teachers and students, place of instruction; disciples of a teacher, body of followers, sect,” 
from Greek skhole “spare time, leisure, rest ease; idleness; that in which leisure is employed; learned discussion;” also “a place for lectures, school;” originally “a holding back, a keeping clear,” from 
skhein “to get” (from PIE root 
*segh- “to hold, hold in one’s power, to have;” see 
scheme (n.)) + 
-ole by analogy with 
bole “a throw,” 
stole “outfit,” etc.