1. Involving four parties
   - four-party

See also: many-sided, multilateral

• unacknowledged
• unacquainted
• unacquainted with
• unacquisitive
• unactable
• unadaptability
• unadaptable
• unadapted
• unaddicted
• unaddressed
• unadjustable
• unadjusted
• unadmonished
• unadoptable
• unadorned
• unadulterated
• unadventurous
• unadvisable
• unadvised
• unadvisedly
• unaerated
• unaesthetic
• unaffected
• unaffectedly
• unaffectedness