" jointly "

1: in or by combined action or effort;

  * e.g., " ... we always purchase our mother's birthday present jointly "

•  Synonyms : 

•  concertedly,

•  conjointly,

•  hand in glove,

•  together

•  Antonyms : 

•  apart,

•  independently,

•  individually,

•  separately,

•  severally,

•  single-handed,

•  single-handedly,

•  singly,

•  solely,

•  unaided,

•  unassisted,

•  unilaterally

1: used or done by a number of people as a group;

  * e.g., " ... a joint effort by residents of the neighborhood to help reduce crime "

•  Synonyms : 

•  collaborative,

•  collective,

•  combined,

•  common,

•  communal,

•  concerted,

•  conjoint,

•  conjunct,

•  cooperative,

•  multiple,

•  mutual,

•  pooled,

•  public,

•  shared,

•  united

•  Antonyms : 

•  exclusive,

•  individual,

•  one-man,

•  one-sided,

•  one-way,

•  single,

•  sole,

•  solitary,

•  unilateral