bur·den
[bur-dn]

–noun
1.that which is carried; load: a horse’s burden of rider and pack.

2. that which is borne with difficulty; obligation; onus: the burden of leadership.

3. Nautical .
     a. the weight of a ship’s cargo.
     b. the carrying capacity of a ship.

4. Mining . overburden ( def. 3 ) .

5. Metallurgy . the minerals charged into a blast furnace or steelmaking furnace.

6. Accounting . overhead ( def. 6 ) .

–verb (used with object)
7. to load heavily.

8. to load oppressively; trouble.