You are obese if you are very fat or overweight. Obese people often have health problems because of their size.
Something is odd if it is different to usual, or is a bit strange. In a group of things, something that is different is called the odd one out. The man in the picture is wearing odd socks. Mathematically, a number is odd if it is not a multiple of two.
Offshore means in the water some distance from the shore, the sandy area where land meets a body of water such as an ocean or a lake.
Something is old if it has existed for a very long time. Something that is really, really old is called ancient. When people get old they get grey hair and wrinkles.
Something is old fashioned if it looks like it belongs in the past, and doesn't fit in with things around it. Clothes can be old fashioned, and behaviour can be old fashioned too. Old fashioned things can also be called retro.
Something is opaque if you can't see through it. Most things are opaque. The term is most often used to describe stockings that are not transparent.
Something is open if you can go through it or into it. The door in the picture is open. The opposite of open is closed.
Something is ordinary if there is nothing outstanding about it. Something is ordinary if you don't really notice it as you pass by.
Something is original if it has never been done before. An idea is original if it has never been thought of before, and a painting is original if it is the first time that picture has been painted. If something has been made as a copy or modified from something else, the thing it has been copied from is the original. The dress in the picture is original, because it is hand-made and there is no other dress like it.