Just for fun, and in no particular order, these are some of my favorite words - and their meanings - I've come across over the years.

Juxtaposition
Definition: act of being side-by-side

Masticate
Definition: to chew

Dodecahedron
Definition: a twelve-sided solid

Bivouac
Definition: a temporary military camp (pronounced 'biv-oo-ak' or 'biv-wak')

Contentious
Definition: argumentative, quarrelsome

Pneumonoultramicroscopicsilicovolcanoconiosis
Definition: invented word used to refer to a lung disease caused by silica dust

alpha-D-Glucopyranosyl beta-D-fructofuranoside
Definition: chemical name for sucrose, aka. table sugar