Possible Clues:

• Antonyms: Abbr.
• They sometimes attract: Abbr
• They may be polar (Abbr.)
• Antonyms: Abbr
• Enemies, in slang
• Pos. and neg
• Plus and minus: Abbr
• Antonyms, for short
• Antonyms (abbr.)
• Pos. and neg., e.g.