W2S2 [ˈmembəʃıp US -ər-] n
1.) [U]
when someone is a member of a club, group, or organization
membership of
Greece first applied for membership of the EU in 1975.
membership in AmE
I forgot to renew my membership in the sailing club.
You should carry your membership card with you at all times.
Membership fees are being increased this year.
2.) [singular also + plural verb British English]
all the members of a club, group, or organization
The membership voted to change the rules about women members.
3.) [singular]
the number of people who belong to a club, group, or organization
We're trying to increase our membership.
The club now has a membership of over 2,000.
COLLOCATES for sense 1
apply for membership
renew your membership (=apply to become a member again after your membership has ended)
union/church/party etc membership (=membership of a particular group)
full membership (=membership with all the rights that can be allowed to members)
membership card
membership fees

Dictionary of contemporary English. 2013.