The concept of arcbody was introduced in  as a generalization of prime tangles used by Lickorish and Bleiler[l]. The pair (A, l), where A is a compact 3-manifold with boundary ∂A, and l is a 1-submanifold properly embedded in A, is an arcbody if:
(i) the inclusion ∂ A – l ↪ A – l is monic, i.e. A – l has incompressible boundary;
(ii) no component of (A, l) is homeomorphic to (D2, 0) × I or (D2, 0) × S1; and
(iii) every sphere of ∂A intersects l.