T-shirt BrE AmE , tee-shirt /ˈtiː ʃɜːt $ -ʃɜːrt/ noun [countable]
[ Date: 1900-2000 ; Origin: Because it is shaped like the letter T ]
a soft shirt with short ↑ sleeve s and no collar:
She was wearing jeans and a T-shirt.
T-shirt BrE AmE , tee-shirt /ˈtiː ʃɜːt $ -ʃɜːrt/ noun [countable]
[ Date: 1900-2000 ; Origin: Because it is shaped like the letter T ]
a soft shirt with short ↑ sleeve s and no collar:
She was wearing jeans and a T-shirt.
Longman Dictionary of Contemporary English. Longman - Словарь современного английского языка. 2012