From sun and deo; to bind with, i.e. (passively) be a fellow-prisoner (figuratively) -- be bound with.
see GREEK sun
see GREEK deo
1. to tie together, to bind together.
2. to bind or fasten on all sides.
3. to bind just as (i. e. jointly with) another: perfect passive participle ὡς συνδεδεμένοι, as fellow-prisoners (A. V. as bound with them), Hebrews 13:3 (συνδεδεμενος τῷ ὀινοχόω, Josephus, Antiquities 2, 5, 3).