Wordnet 3.0
NOUN (1)
1.
a geological process in which one edge of a crustal plate is forced sideways and downward into the mantle below another plate;
The Collaborative International Dictionary of English v.0.48:
Subduction \Sub*duc"tion\, n. [L. subductio.]
1. The act of subducting or taking away. --Bp. Hall.
[1913 Webster]
2. Arithmetical subtraction. --Sir M. Hale.
[1913 Webster]
WordNet (r) 3.0 (2006):
subduction
n 1: a geological process in which one edge of a crustal plate
is forced sideways and downward into the mantle below
another plate