競
キョウ, ケイ, きそ.う, せ.る, くら.べる, かい, わたなべ
emulate, compete with, bid, sell at auction, bout, contest, race
JLPT2 G4 S20 F610
The relevant seal inscription form is 誩# + 从. 誩 is 言 words (doubled) → verbal disputation. 从 is a variant form of 従 (people in close formation). The combination of elements suggests verbal competition → *compete* → *auction*.
[Full Kanji Etymology List]