底面

(1)the lower side of anything

(2)あるものの下側の面

(3)the bottom side of a geometric figure from which the altitude can be constructed; "the base of the triangle"

(4)高さをそこから描くことのできる幾何学的図形の底の辺

(5)the bottom or lowest part; "the base of the mountain"

(6)底、あるいは最も下の部分

(7)a flat bottom on which something is intended to sit; "a tub should sit on its own base"

(8)何かが座ることを意図する平底

(1)a tub should sit on its own base

(2)桶は桶の底を下にして置くべきだ