ROGET THESAURUS
coexist
Accompaniment
VB
accompany,
coexist, attend, hang on, wait on, go hand in hand with, synchronize, bear company, keep company, row in the same boat, bring in its train, associate with, couple with.
Synchronism
VB
coexist, concur, accompany, go hand in hand, keep pace with, synchronize.
Contiguity
VB
be contiguous, join, adjoin, abut on, march with, graze, touch, meet, osculate, come in contact, coincide,
coexist, adhere, juxtapose, contact, join (unite), link (vinculum).