A hipped roof is sloped in two pairs of directions (e.g. N-S and E-W) compared to the one pair of direction (e.g. N-S or E-W) for a gable roof.

Merriam-Webster Online Dictionary
hip (noun)
- rose hip
hip (noun)
a) the laterally projecting region of each side of the lower or posterior part of the mammalian trunk formed by the lateral parts of the pelvis and upper part of the femur together with the fleshy parts covering them
b) - hip joint
the external angle formed by the meeting of two sloping sides of a roof that have their wall plates running in different directions
hip (interjection)
- used in a cheer hip hip hooray
hip (adjective)
a) having or showing awareness of or involvement in the newest developments or styles
b) very fashionable - trendy
aware or appreciative of something - used with to got hip to their plan
hip (verb)
transitive verb
to make aware - tell inform
hip (noun)
- hipness