To faze is to disconcert or unsettle — it didn't faze him. A phase is a stage in a process, and as a verb means to introduce gradually: phase in, phase out. "It didn't phase me" is the common error, and it is the one to watch because <em>phase</em> is by far the more familiar spelling.
The core difference
An uncommon verb and a very common noun that sound identical.
- faze — disconcert: nothing fazes her. Almost always in the negative.
- phase — a stage: the first phase. As a verb: phase out the old system.
Why faze loses
Faze appears almost exclusively in negative constructions — "didn't faze", "unfazed" — so it is rarely seen and easily displaced by the far commoner phase. Unfazed is worth remembering as the anchor: nobody writes "unphased" for calm, and if that looks wrong, so does "didn't phase me".
Origins
Faze is a nineteenth-century American variant of feeze, to frighten. Phase is from Greek phasis, appearance — as in the phases of the moon, which is where the "stage" sense comes from.
Frequently asked questions
Is it "didn't faze me" or "didn't phase me"?
Didn't faze me. Faze means to disconcert; phase is a stage.
How do I remember it?
Think of unfazed, which nobody spells "unphased". If that looks wrong, so does "phase me".
Where does phase come from?
Greek phasis, appearance — as in the phases of the moon, which gave us the "stage" sense.