Western clothing store; clothes shop
A shop that sells Western-style clothing, as opposed to traditional Japanese garments.
A new Western clothing store opened in front of the station.
tailor; dressmaker; tailor's shop
A person or shop that makes or alters Western clothing; can refer to the business or the craftsperson.
If you want a suit made, that tailor is good.
A tailor or dressmaker, often emphasizing the craft of making clothes; 洋服屋 can refer to a shop that sells ready-made Western clothes as well.
Compound of 洋服 (Western clothing) + 屋 (shop, seller).