Because I’m easily confused, it makes sense for me to have this all in one place. So, as I research and figure this out, I’ll post definitions of local, Indian, and area clothing. A lot of info is taken from Wikipedia and some from personal experience.
Let’s start with…
Shalwaar Kameez: Sometimes called a Punjabi suit, after the Indus valley area called the Punjab. Shalwaar kameez is the outfit comprising the individual components of a shalwaar and a kameez.
Salwar (also spelled salwar, shalwar) are a sort of loose pyjama-like trousers. The legs are wide at the top, and narrow at the bottom. The legs are pleated or gathered into a waistband. There is a drawstring at the top of the waistband to hold up the salwar. The pants can be wide and baggy, or they can be cut quite narrow, on the bias. In the latter case, they are known as churidar.
The kameez is a long shirt or tunic. The side seams (known as the chaak) are left open below the navel, which gives the wearer greater freedom of movement.
In Sri Lanka, it’s more common that the side splits start at the hips. Too high and the abdomen shows, which is generally not considered acceptable among the Muslim community. The shalwaar kameez in Sri Lanka is more common among Muslims than any other community.
Dupatta (in Sri Lanka, called a shawl): When women wear the saalwar kameez, they usually wear a long scarf or shawl called a dupatta around the head or neck. For Muslim women, the dupatta is a less stringent alternative to the chador or burqa (see hijab). For Hindu women (especially those from northern India, where the salwar kameez is most popular), the dupatta is useful when the head must be covered, as in a temple or the presence of elders. For other women, the dupatta is simply a stylish accessory that can be worn over one shoulder or draped around the chest and over both shoulders.
In Sri Lanka, Muslim women typically wear the shawl around the chest and over both shoulders.
Kurta (from Wikipedia): A kurta (or sometimes kurti, for women) is a traditional piece of clothing worn in India, Pakistan, and Afghanistan. It is a loose shirt falling either just above or somewhere below the knees of the wearer, and is worn by both men and women. It can be worn with either a pajaamaa (men), salwar (women), or churidaar (a unisex tight-fitting trouser). They are typically worn in more formal occasions, especially in the case of men, who in South Asia have largely moved to Western clothes as everyday wear.
Churidaar is a unisex tight-fitting trouser.
Pajaamaa are the men’s pants worn with either a kurta or a shalwaar. (Edited to add:) They’re super long slim legged pant that gets bunched up at the ankle area.
Saree or Sari is an extremely versatile garment. It simply consists of a length of material, about six yards in length. The style, color, and texture of this material vary according to region and caste. Different draping styles convey the status, age, occupation, region, and/or religion of the wearer.
In Sri Lanka, it is typically worn either in the Kandyan or Indian style.
Choli (or blouse in Sri Lanka) is the tightly fitted complimentary colored, short blouse worn under a saree. Originally, cholis only covered the front, now they have evolved to include versions covering front and back to midriff. The traditional form is still commonly worn in Rajastan.
Lehanga is a pleated skirt worn mostly in Rajastan. Worn with a choli, it is secured at the waist, leaving the back and midriff bare. A length of fine cotton called a dupatta, completes the ensemble, covering the head.
Sharwani (also spelled Sherwani) is an Indian suit made from heavier material much like western suits. It typically goes to or past the knees, has side slits from the hips down, and has beadwork, sometimes very elaborate, around the collar and down the front opening. Sometimes the beadwork is all over the garment. Regardless, it ranges into the extremely ornate. It’s usually worn with the tight-legged pants called Churidaar. Also usually worn with a dupatta.