Learner's definition of PARTNERSHIP
1 [noncount] : the state of being partners
two people joined in partnership
scientists working in partnership with each other
The company is developing a new car in partnership with leading auto manufacturers in Japan.
The two companies have gone/entered into partnership (with each other).
2 [count] : a relationship between partners
Their marriage is a partnership that has remained strong despite family illness.
The singing duo has maintained a successful partnership for 20 years.
a notable partnership between two experienced scientists in the field
3 [count] : a business that is owned by partners