A steam iron is an electric iron that produces steam from water that you put into it. The steam makes it easier to get the creases out of your clothes.
steam iron in British English
noun
an electric iron that emits steam from channels in the iron face to facilitate the pressing and ironing of clothes, etc, the steam being produced from water contained within the iron
steam iron in American English
US
an electric iron that forms steam from water and releases it through the soleplate onto the material being pressed
Examples of 'steam iron' in a sentence
steam iron
For Tara's birthday in September, she bought her a steam iron.
Cathy Kelly JUST BETWEEN US (2002)
Don't ever let anyone smarten you up, don't ever let Lisa run a steam iron over you.
Cleary, Jon MURDER SONG (2002)
I've got a steam iron, which makes all the difference, but still, it's a lot of work.