The side of something or someone is a part that is not on the mainline or main direction. To side with someone is to stand near them as a supporter or to speak out for them or their ideas. In sports there are two teams that are referred as opposite sides. If I am moving in a particular direction, let us say north, then a side step would be to the east or the west. South would be a back step. None of these are up or down.
The sport playing area can be defined by lines on the ground or floor. Outside of that area are the sidelines. A sidecar is an attachment beside the main motorcycle and can be detached. It is used to transport an extra passenger. I recall often seeing sidecars attached to motorcycles in old war movies. The relatively long, low, storage cabinet with a flat top that matches the dining room table is a sideboard.
A sidelong glance is one of those ‘what were you thinking?’ or a highbrow look of condescension. It is an expression of judgment. To come along side can refer to a ship or boat coming parallel to a landing place or other boat or ship. It can also refer to people where you could come alongside of me as I walk or run. If I am still you might sidle up to me. A right angle triangle has one side that is longer than the other two.
A sidebar is a small article, usually in a box, the contents of which amplify some part of the main article. Some computer displays have sidebar information, like at the top of a Word page, where often used tools and such are in easy reach. In a conversation, someone might bring up a topic or issue that is too far from the main point, so that would be a side issue. A stream that leaves the river to run beside it but rejoins, is called an oxbow
When someone is sidetracked they are off the main course, the way Little Red Riding Hood wandered off the path to pick flowers. Becoming sidetracked is a way to sustain procrastination while still appearing to look busy. When a project or job goes sideways it means it has veered way off track. It usually means a severe interruption or distraction. What causes you to get sidetracked?
