WordNet (r) 3.0 (2006):

stick together
    v 1: be loyal to one another, especially in times of trouble;
         "The two families stuck together throughout the war" [syn:
         stick together, stay together]

Moby Thesaurus II by Grady Ward, 1.0:

107 Moby Thesaurus words for "stick together":
   accouple, accumulate, adhere, agglomerate, agglutinate, amass,
   articulate, assemble, associate, band, be consistent, be the case,
   be true, be truthful, bind, bond, bracket, braze, bridge,
   bridge over, bunch, cement, chain, clap together, clasp, cleave,
   clinch, cling, cling to, clot, cluster, coagulate, cohere, collect,
   combine, comprise, concatenate, conform to fact, congeal,
   conglobulate, conglomerate, conjoin, conjugate, connect, copulate,
   couple, cover, embrace, encompass, freeze to, fuse, gather, glue,
   grasp, grow together, gum, hang on, hang together, hold, hold good,
   hold on, hold together, hold true, hold up, hold water, hug,
   include, join, knot, lay together, league, link, lump together,
   marry, marshal, mass, merge, mobilize, pair, paste, persist,
   piece together, prove out, prove to be, prove true, put together,
   remain valid, roll into one, set, solder, solidify, span, splice,
   stand the test, stand up, stay, stay put, stick, take hold of,
   take in, tape, tie, unify, unite, wash, weld, yoke