In GUI (inc. web page) context, alignment refers to the positioning of visual elements. Three possibility of alignment left, right, and center.
In a memory addressing context, alignment is the placement of data or code at memory addresses that are multiples of some (usually small) power of 2, for example having an array start at a 16-byte boundary with C++
alignas(16) int foo;. This means the address will end with at least 4
For this meaning, prefer the memory-alignment tag.