Lackadaisical

1.  adj.
Definition: lacking enthusiasm and determination; carelessly lazy
Example: lackadaisical effort
Sentence:  My dog is so lackadaisical that he won't even get up to eat: we have to feed him by hand.
Pronunciation: lack-uh-day-sih-cahl
Notes:  This word is only used to describe people, events, or animals, like so many other words.  You CAN'T SAY "lackadaisical homework," for example.  It has to describe something that can do things (an event can change, etc.).

Eradicate

1.  verb

Definition:  to put do an end to, destroy; to pull up by the roots

Example: eradicate poverty

Sentence:  Scientists have used vaccines and other medicines to eradicate malaria in some countries.

Notes:  The word eradicate (pronounced err-aah-dih-cate) comes from the Latin radice, or roots.  Eradicate means to take out by the roots, coming right from the Latin.

Inconspicuous

1.  adj.
Definition: Not clearly visible or attracting attention; not conspicuous
Example: an inconspicuous garden
Sentence: The inconspicuous spy snuck up behind the criminal, knocked him out, and brought him to the station for questioning.
Notes:  This word is pronounced in-cuhn-spih-cu-us.  It is a fabulous word, and I recommend it for every use!

Archaic

1.  adj.
Definition: very old or old-fashioned
Example: an archaic hairstyle
Sentence: The original computers seem archaic compared to today's: they used to take up entire rooms!
Notes: Archaic almost means antique, just older.  An archaic antique is a different story!

Desultory

1. adj.

Definition:  lacking a plan, purpouse, or enthusiasm; not connected with the main subject

Example: a desultory house

Sentence: Our desultory expedition ended in disaster when noone knew where to meet at the end.

Concatenate

1. v.

Definition: to link together, in a series or a chain

Example: concantenate a stapler and a tape dispenser

Sentence:  I concantenated two words to make a new, unique one.

Derisory

1. adj.
Definition: ridiculously small or inadequate
Example: a derisory pay raise
Sentence: I heard of his derisory effort to stop her from going on vacation.
Notes:  This word is pronounced with a long "i" as opposed to a short one.  It is very easy to mess up, so be careful!  Also, it normally describes things that are said or done, not objects.

Supercilious

1. adj.
Definition: Behaving or looking as though one thinks one is superior to others
Example:  the supercilious celebrity
Sentence:  At the party, it was easy to see the supercilious hostess in the crowd.
Notes:  Probably one of the most famous uses of this word is in the first chapter of F. Scott Fitzgerald's "The Great Gatsby" in the sentence "Now he was a sturdy, straw haired man of thirty with a rather hard mouth and a supercilious manner."

Persnickety

1. adj.

Definition: turning too much attention on trivial or minor details

Example: the persnickety artist

Sentence: The persnickety chef gently placed the delicate garnish on the plate.

Notes:  Since I was really little, I've always loved this word.  I remember I used to be so persnickety about putting a sticker so that it completely covered the outline of where it was supposed to go!

Obfuscatory

1. adj.

Definition: intended to conceal the truth by confusion

Example: the politician's obfuscatory speech

Sentence: My brother's obfuscatory excuse to the teacher about being late for class confused her so much he didn't get detention.

Notes: This word at first seems serious, but as you say it becomes funnier and funnier.  The word itself is obfuscatory and confusing!  It's the perfect word in a situation when you need it.

Gossamer

1.  adj.
Definition: light, delicate, or insubstantial
Example: a butterfly's wings
Sentence: The gossamer flower floated down from the air where the wind had blown it.
Notes:  I love this word because of the way it sounds.  It is a delicate word and is beautiful when used properly.  Its gentle sound gives away its meaning from the beginning, so it's easy to remember the meaning.