The 1980s mid-to-late 1980s
The Shoulder-Pad Blazer
A structured, single- or double-breasted jacket built around a genuinely wide, padded shoulder line - the single garment most responsible for putting the decade's power silhouette on real office floors.
Strip the power silhouette down to the one garment that actually did the work of putting it in offices nationwide, and you get this blazer: structured shoulders built out with real internal padding, a nipped, often belted waist, and a hem that hits somewhere between hip and mid-thigh, worn over a blouse, bodysuit, or dress rather than as part of a matched suit necessarily. Unlike a lot of runway-driven silhouette stories, this specific garment made it into department stores and office closets essentially unchanged from its more dramatic couture inspiration - the padded shoulder translated directly and immediately into ready-to-wear.
The construction underneath is worth understanding on its own terms: shoulder pad construction builds actual structured padding - foam, felted wool, or layered fabric shapes - into the shoulder seam itself, widening the visible shoulder line well beyond a wearer's natural anatomy without needing to alter anything else about how the jacket fits. That's a genuinely different engineering problem than most earlier decades' tailoring, which mostly worked with a woman's existing shoulder line rather than actively rebuilding it outward.
Donna Karan's version, more wearable and less severe than Mugler or Montana's runway extremes, is the one that actually shows up in most period office photographs, and I think that gap between runway origin and everyday execution is the real story of this garment. It's the power dressing idea in its single most portable, most purchasable form - a woman could own exactly one of these and instantly signal the whole silhouette's authority, without needing the rest of a couture-level wardrobe to back it up.