/seuhb tend", sub-/ , v.t.
1. Geom. to extend under or be opposite to: a chord subtending an arc.
2. Bot. (of a leaf, bract, etc.) to occur beneath or close to.
3. to form or mark the outline or boundary of.
[ 1560-70; subtendere to stretch beneath, equiv. to sub- SUB- + tendere to stretch; see TEND 1 ]