Wiktionary
alt. (context US English) A sleeveless sweater, commonly knit in argyle. n. (context US English) A sleeveless sweater, commonly knit in argyle.
Wikipedia
A sweater vest is an item of knitwear that is similar to a sweater, but without sleeves, usually with a low-cut neckline. They were popular in the 20th century, particularly in the 1970s in the UK, and are again growing in popularity in this century.
The name "tank top", recorded in English since 1968, derives from its resemblance to a tank suit, a style of one-piece women's swimsuit with shoulder straps, so called since the 1920s, because it was worn in a "swimming tank", an obsolete term for a swimming pool. In American English, a tank top refers to a sleeveless shirt.
Usage examples of "sweater vest".
He has on a tweed sport jacket, cashmere sweater vest, cotton chambray shirt, tie, Paul Stuart, Agnes B.
A man in a sweater vest tipped a conductor's cap, smiled, and continued sorting the packages.
He wore a bright orange sweater vest over a pink short-sleeved golf shirt and his gait tended to a lilt as if he were still wearing cleats.
I couldn't resist reaching out and plucking a splinter of wood from his sweater vest.
He wore a blue oxford shirt under a gray V-neck sweater vest, and khaki pants and L.
On Tuesday I wore my navy blue wool skirt and knit sweater vest with a white starched blouse and penny loafers, so I would look more studious.
They were mostly Chinese, led, as every week, by the same old man in a gray knit cap and sweater vest.
He was wearing wide-wale blue corduroy trousers and a navy blue sweater vest over a red plaid shirt.
After a brief wait, it was opened by a middle-aged man with the look of a stereotypical college professor, sweater vest over a button up oxford, brown slacks, and brown loafers.