'co-optation' definitions:

Definition of 'co-optation'

noun

The selection of a new member (usually by a vote of the existing membership) [syn: co-option, co-optation]

noun

The act of appointing summarily (with or without the appointee's consent) [syn: co-option, co-optation]

From: GCIDE

co-optation \co-optation\, cooptation \co`["o]p*ta"tion\, n. [L. cooptatio.] The act of choosing; selection; choice. [Obs.] [1913 Webster]
The first election and cooptation of a friend. --Howell. [1913 Webster]
2. the selection of a new member (usually by a vote of the existing membership). See co-opt[2].
Syn: co-option. [WordNet 1.5]
3. the act of appointing summarily (with or without the appointee's consent).
Syn: co-option. [WordNet 1.5]