Maglione vs. maglia vs. pullover vs. felpa

Italian has several words for various types of upper body garments similar to sweaters. While there is some overlap, each term has specific connotations and usage.

Maglione

'Maglione' refers to a heavy, warm sweater typically worn in cold weather.
Ho bisogno di un maglione pesante per l'inverno.
(I need a heavy sweater for winter.)
Mia nonna mi ha fatto un maglione di lana.
(My grandmother made me a wool sweater.)

Maglia

'Maglia' is a more general term that can mean any knitted garment, from a light sweater to a T-shirt.
Indosso una maglia leggera in primavera.
(I wear a light sweater in spring.)
Ho comprato una maglia a maniche corte.
(I bought a short-sleeved shirt.)

Pullover

'Pullover' is a loanword from English, typically referring to a sweater that is pulled over the head.
Mi piace indossare un pullover con i jeans.
(I like wearing a pullover with jeans.)
Ho un pullover a collo alto per le giornate fredde.
(I have a turtleneck pullover for cold days.)

Felpa

'Felpa' usually refers to a sweatshirt or hoodie, often made of fleece or similar soft, warm fabric.
Indosso una felpa quando vado a correre.
(I wear a sweatshirt when I go running.)
Ho comprato una felpa con cappuccio per mio figlio.
(I bought a hooded sweatshirt for my son.)

Summary

While 'maglione' is a heavy sweater, 'maglia' can be any knitted garment. 'Pullover' specifically refers to a sweater pulled over the head, and 'felpa' is typically a sweatshirt or hoodie. Context and specific garment characteristics often determine which word is most appropriate.