Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
subvectĭo, ōnis, f. [subveho], a carrying, transporting, conveying, conveyance: frumenti, Liv. 44, 8; Tac. A. 13, 51 fin.
Plur.: durae subvectiones, Caes. B. G. 7, 10: marinae, Vitr. 1, 5, 1.