A little known but extremely useful resource for Latin composition is the digitization of Lewis & Short done at the University of Chicago:

http://perseus.uchicago.edu/Reference/lewis.html

Search the FULL TEXT of this dictionary for an English word to find every entry in Lewis & Short where that English word appears. Sort through the various Latin words that pop up until you find one that approximates what you want to say.

For example, a search for “silk” yields the following cornucopia of terms, all classically attested, or at least attested within the generous limits of L&S.

1. birrus n., Aug. Serm. Divers. 49), = πυρρός (of yellow color), a cloak to keep off rain (made of silk or wool)

2. bombycinus , a, um, adj. bombyx, of silk, silken (cf. sericus): vestis, Plin. 11, 22, 26, § 76: panniculus,

3. bombycinus (page 243) 14, 24; Dig. 34, 2, 23, § 1.—Subst.: bombȳcĭna, ōrum, n., silk garments, Mart. 11, 50, 5; 8, 68, 7; App. M. 8, p. 214, 6.—And

4. bombycinus (page 243) 11, 50, 5; 8, 68, 7; App. M. 8, p. 214, 6.—And bombȳcĭnum, i, n., a silk texture or web, Isid. Orig. 19, 22, 13. bombylis , is,

5. bombyx (page 243) (f., Plin. 11, 23, 27; Tert. Pall. 3), = βόμβυξ. The silk-worm, Plin. 11, 22, 25, § 75 sqq.; Mart. 8, 33, 16; Serv. ad Verg. G. 2,

6. bombyx (page 243) Verg. G. 2, 121; Isid. Orig. 12, 5, 8; 19, 27, 5.— Meton. That which is made of silk, a silken garment, silk: Arabius, Arabian (the best), Prop. 2, 3, 15: Assyria bombyx,

7. bombyx (page 243) Orig. 12, 5, 8; 19, 27, 5.— Meton. That which is made of silk, a silken garment, silk: Arabius, Arabian (the best), Prop. 2, 3, 15: Assyria bombyx, Plin. 11, 23, 27, §

8. holosericus (page 859) holosericus , a, um, adj., = ὁλοσηρικός, all of silk: vestis, Lampr. Heliog. 20; Vop. Aur. 45; id. Tac. 10; Cod. Th. 15, 9, 1. —Collat. form,

9. metaxa (page 1140) metaxa or mătaxa, ae, f., = μέταξα and μάταξα, raw silk, the web of silkworms. Lit., Dig. 39, 4, 16; Cod. Just. 11, 7,

10. necydalus (page 1196) necydalus , i, m., = νεκύδαλος (deathlike), the larva of the silk-worm, in the stage of metamorphosis preceding that in which it receives the name of bombyx: primum eruca fit, deinde, quod vocatur bombylius, ex eo necydalus, ex hoc in sex mensibus bombyx,

11. Seres (page 1678) 11, 27, 11; Claud. in Eutr. 2.— sērĭ-cum, i, n., Seric stuff, silk, Amm. 23, 6, 67; Sol. 50; cf. Isid. Orig. 19, 17, 6; 19, 27, 5;

12. sericarius (page 1678) or belonging to silks: textor, Firm. Math. 8: NEGOCIATOR, Inscr. Orell. 1368; 4252.—As substt. SERICARII, silk- dealers, Inscr. Fabr. p. 713, 346.— SERICARIA, ae, f., a slave who took care of silk, Inscr. Orell.

13. sericarius (page 1678) SERICARII, silk- dealers, Inscr. Fabr. p. 713, 346.— SERICARIA, ae, f., a slave who took care of silk, Inscr. Orell. 2955. sericatus , a, um, adj.

14. sericoblatta (page 1679) sericoblatta , ae, f. Sericus, a garment of purple silk, Cod. Just. 11, 8, 10; Cod. Th. 10, 20, 13; 10, 20, 18. sericum , i,

15. vellus (page 1965) Calp. Ecl. 2, 7.— Of woolly material. Wool, down: velleraque ut foliis depectant tenuia Seres, i. e. the fleeces or flocks of silk, Verg. G. 2, 121.— Of light, fleecy clouds: tenuia nec lanae per caelum vellera ferri,

English search is not, I believe, available on Logeion, which is the successor to this site. Hopefully this older one will be kept around for a good while longer. I don’t know anything as good online for searching in English for Latin words. Thanks to Helma Dik and the U. Chicago team for all their work!