3. Tacky

Two main meanings 
There is the actual meaning
and the figurative meaning. 

The actual meaning of tack
is that it is an adjective used to describe a sticky substance.
Tape is tacky 
Honey, mollases, glue
All are tacky 
Tack is tacky
Blue tac is that stuff you can put on the back of light objects to get it to STICK to the wall 
Tacks, small sharp pins or nails with a wide head, are tacky

Then there is the more figurative meaning of the tacky adjective  
A person can be tacky 
So can a room 
Or anything that, as a quality 
Is in poor taste
Taste, in this sense
means aesthetic taste 
so it deals with the question of beauty.
When something is in poor taste it is tacky.
Poor taste = tacky
Equals something with low aesthetic value- it is not beautiful

A tacky person 
could be someone wearing a terrible outfit
think huge waist belts, ugly sweaters at Christmas, women in heels at the grocery store 
Cheap jewelry or clothes 
that is supposed to look nicer than it is   
Like a knock-off Rolex or a knock off purse 

But it is more than clothes. 
Imagine a room.
A room with a futon.  
Behind the futon
There are trinkets and knick-knacks.
To the side of the futon 
Is a weird colorful lamp 
and a fake plant.
On the other side
of the room 
is a couch with a plastic cover.
And above that couch
in the center of the room 
is a framed reprint in the center of the room 
Of the Mona Lisa