Maçaneta vs. puxador
The words maçaneta and puxador generally refer to the object used to open a door or drawer. The main difference lies in the mechanism (whether it turns or is fixed) and regional preferences between Brazil and Portugal.
Maçaneta
B1In Brazil, maçaneta determines the function: it is a handle that you must rotate, twist, or turn to release a latch, usually found on standard walking doors. In Portugal, this word is used more specifically to describe a spherical doorknob or a small lever handles, though it is less generic than in Brazil.
Ela girou a maçaneta bem devagar para não fazer barulho.
(She turned the doorknob very slowly so as not to make noise.)
A maçaneta do banheiro está emperrada e não gira.
(The bathroom handle is stuck and won't turn.)
Ele limpou a maçaneta de bronze com um pano especial.
(He cleaned the brass doorknob with a special cloth.)
Puxador
B1In Portugal, puxador is the standard, generic term for almost any door handle, regardless of whether it turns or is fixed. In Brazil, puxador refers strictly to a fixed handle that does not rotate, such as those found on drawers, cupboards, refrigerators, or sliding doors.
O puxador da gaveta se soltou na minha mão.
(The drawer handle came loose in my hand.)
Em Portugal, é comum chamar a peça da porta principal de puxador.
(In Portugal, it is common to call the main door part a handle.)
Precisamos comprar um puxador novo para a porta de correr.
(We need to buy a new handle for the sliding door.)
O bebê não consegue alcançar o puxador da geladeira.
(The baby cannot reach the fridge handle.)
Summary
Use maçaneta in Brazil for any door handle that rotates or turns to unlatch. Use puxador in Brazil only for fixed handles that you pull (like on furniture or glass doors). In Portugal, puxador is the most common word for all door handles, while maçaneta usually refers specifically to a knob shape.