Definitions:

1. Shows mutual interaction or exchange. PRONOUN
   • The two cats were grooming each other by the window.
2. Used to indicate that two or more people, animals, or things are performing an action on one another or in relation to one another. PRONOUN
   • They always help each other with their homework.
3. Used to show that each person in a group of two or more people does something to the others. PRONOUN
   • They kept looking at each other and smiling.

Synonyms:

• jointly
• mutual
• mutually
• one another
• reciprocal
• together