WordNet sense 1 ((contract bridge) the highest bid becomes the contract setting the number of tricks that the bidder must make):

declaration

WordNet sense 2 (engage by written agreement):

sign, sign up, sign on

WordNet sense 3 (squeeze or press together):

compact, compress, constrict, press, squeeze, compact, compress

WordNet sense 4 (enter into a contractual arrangement):

undertake

WordNet sense 5 (a variety of bridge in which the bidder receives points toward game only for the number of tricks he bid):

contract bridge

WordNet sense 6 (compress or concentrate):

concentrate, condense

WordNet sense 7 (make or become more narrow or restricted):

narrow

WordNet sense 8 (reduce in scope while retaining essential elements):

abbreviate, abridge, cut, foreshorten, reduce, shorten

WordNet sense 9 (become smaller or draw together):

shrink

WordNet sense 10 (be stricken by an illness, fall victim to an illness):

get, take