take the place or move into the position of; "Smith replaced Miller as CEO after Miller left"; "the computer has supplanted the slide rule"; "Mary replaced Susan as the team's captain and the highest-ranked player in the school"
place in a place where something cannot be removed or someone cannot escape; "The parents locked her daughter up for the weekend"; "She locked her jewels in the safe"
close with or as if with a tight seal; "This vacuum pack locks in the flavor!"
a mixture containing two or more metallic elements or metallic and nonmetallic elements usually fused together or dissolving into each other when molten; "brass is an alloy of zinc and copper"