קְטַר (qᵉṭarket-ar'noun|masculinejoint)
[Arc] קְטַר ETCBC: קְטַר‎ (subs|knot) OSHL: xs.af.ab TWOT: 2970 GK: H10626 Greek: σύνδεσμος
Derivation: (Aramaic) from a root corresponding to קָטַר;
Strong's: a knot (as tied up), i.e. (figuratively) a riddle; also a vertebra (as if a knot)
KJV: doubt, joint.