A verb appearing in its past form echant in the phrase im Narvi hain echant “I, Narvi, made them” (LotR/305). In notes on this phrase Tolkien said the literal meaning was “shaped-out”, and the verb stem was echad- derived from ✶et-kat- “out-shape, form” (PE17/42). In drafts of these notes the past form was glossed “cut out, shaped”. The Etymologies of the 1930s had the [Noldorin] infinitive form echedi “fashion, shape” derived from ᴹ✶et-kat under the root ᴹ√KAT “shape” (Ety/KAT; EtyAC/KAT).
Neo-Sindarin: For purposes of Neo-Sindarin, I would assume this verb means “make, fashion” particularly by altering the shape of something, such as by carving wood or molding clay. I further assume that this verb replaces the more basic primitive verb ✶kat- “shape” in Sindarin. However, it is possible that echad- is even more limited in meaning to “shape by taking things out”, and ✱cad- exists as a more general Sindarin verb for “to shape”.
A noun for “camp” appearing as an element in the name Echad i Sedryn “Camp of the Faithful” (UT/153). It might be a combination of √ET “out” and √KHAD “sit”, though if it were it should be ✱✱echadh.