ثغم4 اثغم It (a valley) produced the kind of plant called ثَغَام: (K:) or abounded therewith. (A, TA.) b2:  And (tropical:)  It (the head) became like the ثَغَامَة in whiteness. (K, TA.) ثَغَامٌ A kind of plant, (S, Msb, K, TA,) generally (Msb) found in the mountains, (S, Msb,) having a green stem, (TA,) which becomes white when it dries, (S, Msb, TA,) and to which hoariness is likened; (S, Msb; [Golius, app. misled  by a false reading in a copy of the S, says “ simile  anetho; ”]) it has a thick [head, or blossom, such as is called] سَنَمَة, and [it is said that [it does not grow save upon a black mountain-top, and is found in Nejd and Tihámeh: (TA:) A 'Obeyd  says that it is a kind of plant, (TA,) IF, that it is a tree, (Msb,) with a white blossom and fruit, (Msb, TA,) to which hoariness is likened: (TA:) it is called in Persian درمنه; (K; [written in different copies of that work دِرَمْنَه and دَرَّمْنَه and دَرَمْنَه; the last of which is said in the TA to be the right reading; a word said to mean wormwood, and hyssop; or, accord. to Meninski, as mentioned by Freytag, zedoary; but this last is called in Persian زُرُنْبَا, with which word درمنه may have been confounded;]) or درمنه اسبيد, (S,) or دَرْمَنَه إِسْپِيد, in which [SM thinks] the former word is a contraction of دَرْمِيَانَه; the two together meaning “ in the middle white: ” (TA:) the n. un. is with ة: (S, K:) and ↓ أَثْغَمَآءُ is a quasi-pl. n.; (K;) as though the اء were a substitute for the ة of أَثْغِمَةٌ. (TA.) ثَاغِمٌ A colour white like the ثَغَام: (K:) in the L, a head wholly white. (TA.) أَثْغِمَآءُ: see ثَغَامٌ.