Brachiopods, phylum Brachiopoda, are a phylum of trochozoan animals that have hard "valves" (shells) on the upper and lower surfaces, unlike the left and right arrangement in bivalve molluscs. Brachiopod valves are hinged at the rear end, while the front can be opened for feeding or closed for protection. Two major categories are traditionally recognized, articulate and inarticulate brachiopods. The word "articulate" is used to describe the tooth-and-groove structures of the valve-hinge which is present in the articulate group, and absent from the inarticulate group. This is the leading diagnostic skeletal feature, by which the two main groups can be readily distinguished as fossils. Articulate brachiopods have toothed hinges and simple, vertically oriented opening and closing muscles. Conversely, inarticulate brachiopods have weak, untoothed hinges and a more complex system of vertical and oblique (diagonal) muscles used to keep the two valves aligned. In many brachiopods, a stalk-like pedicle projects from an opening near the hinge of one of the valves, known as the pedicle or ventral valve. The pedicle, when present, keeps the animal anchored to the seabed but clear of sediment which would obstruct the opening.

ब्रैकियोपोडा (Brachiopoda) अकशेरुकी प्राणियों का संघ है जिसके सभी सदस्य समुद्री प्राणी हैं। इस संघ के प्राणी द्विक्पाटी (bivalve) कवच (shell), अखंड (unsegmented) देवगुहा, द्विपार्श्वी (bilaterial) तथा स्पर्शकयुक्त मुख खाँचा वाले हैं। ये द्विपार्श्व, असममित प्राणी हैं।