side

Concise Oxford English Dictionary © 2008 Oxford University Press:
side/sʌɪd/

▶noun

• 1 a position to the left or right of an object, place, or central point.

• 2 either of the two halves of something regarded as divided by an imaginary central line.

• 3 an upright or sloping surface of a structure or object that is not the top or bottom and generally not the front or back.

  ■ each of the flat surfaces of a solid object.

  ■ either of the two surfaces of something flat and thin, e.g. paper.

  ■ either of the two faces of a record or the corresponding parts of a length of audio tape.

• 4 a part or region near the edge and away from the middle.

  ■ each of the lines forming the boundary of a plane rectilinear figure.

• 5 a person or group opposing another or others in a dispute or contest.

  ■ a sports team.

  ■ the cause, interests, or attitude of one person or group.

• 6 a particular aspect: he had a disagreeable side.

  ■ a person's kinship or line of descent as traced through either their father or mother: Richard was of French descent on his mother's side.

• 7 Brit. informal a television channel.

• 8 [as modifier] subsidiary or less important: a side chapel.

• 9 (also side spin) horizontal spinning motion given to a ball, especially by hitting it on one side.

• 10 Brit. informal a boastful or pretentious manner or attitude.

▶verb (side with/against) support or oppose in a conflict or dispute.

– phrases
from side to side

• 1 alternately left and right from a central point.

• 2 across the entire width; right across.

on the side

• 1 in addition to one's regular job.

• 2 secretly, especially as an illicit sexual relationship.

• 3 served separately from the main dish.

side by side close together and facing the same way.
side on on, from, or towards the side.
take sides support one person or cause against another or others.

– derivatives
-sided adjective,
-sidedly adverb,
-sidedness noun,
sideless adjective,
sideward adjective & adverb,
sidewards adverb.

– origin OE sīde ‘left or right part of the body’, of Gmc origin, prob. from a base meaning ‘extending lengthways’.