1.  juxtaposition(n = noun.act) apposition, collocation - the act of positioning close together (or side by side); "it is the result of the juxtaposition of contrasting colors"
Derived form verb juxtapose₁

2.  juxtaposition(n = noun.location) - a side-by-side position;
Derived form verb juxtapose₁

   A placing or being placed in nearness or contiguity, or side by side; as, a juxtaposition of words. [1913 Webster]

N  contiguity, contact, proximity, apposition, abuttal, juxtaposition, abutment, osculation, meeting, appulse, rencontre, rencounter, syzygy, coincidence, coexistence, adhesion, touching, (touch), borderland, frontier, tangent, abutter, contiguous, touching, in contact, conterminous, end to end, osculatory, pertingent, tangential, hand to hand, close to, with no interval.