Shared DNA: 1,655 cM across 46 segments.
Can someone that shows this as one of my matches on AncestryDNA be a half sibling?
Half-sibling is one of the possibilities. If you go to The Shared cM Project 3.0 tool v4, you 'll see that the full list of options include:
Grandparent Aunt / Uncle Half Sibling Niece / Nephew Grandchild
You may be able to eliminate some of these if you know the age difference between the two matches.