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.