Extended Strong's Greek Lexicon (Abbott-Smith based)
to agree
Usage: συν-τίθημι [in LXX: 1Ki.22:13 (קָשַׁר), etc. ;] to place or put together, in various senses. Mid., __(a) to observe, perceive; __(b) to determine, agree, covenant: with inf., Luk.22:5; before τοῦ, with inf., Act.23:20; before ἵνα, Jhn.9:22.† συν-επι-τίθημι, [in LXX for שִׁית, etc. ;] to help in putting on. Mid., to join in attacking (Thuc.): Act.24:9 (RV, joined in the charge).† (AS)