bargaining, diplomacy, mediation, parley.
abbreviation, abdication, aberration, ablation, abnegation, abomination, abrogation, acceleration, acclamation, acclimation, accommodation, accreditation, accumulation, accusation, accusation, acidification, activation, adaptation, adjudication, administration.
Your query has returned 217 words, which include anagrams of negotiation as well as other shorter words that can be made using the letters included in negotiation.
The words in this list can be used in games such as Scrabble, Words with Friends, Wordscapes and other similar games.