ذهن1 ذَهِنَ, (MA, TA,) aor. ـَ (TA,) inf. n. ذِهْنٌ and ذَهَنٌ, (MA, KL,) He was, or became, intelligent, possessed of understanding, sagacious, acute, skilful, knowing, (MA, KL, PS, TA,) and endowed with a retentive mind. (KL, PS.) Yousay, اِذْهَنْ إِلَى مَا أَقُولُ Understand thou what I say. (TA.) And هُوَ لَا يَذْهَنُ شَيْئًا He does not understand anything. (TA.) And ذَهِنْتُ كَذَا وَ كَذَا I understood such and such things. (TA) And ذَهِنْتُ عَنْ كَذَا I understood from such a thing. (TA.) A2:  ذَاهَنَنِى فَذَهَنْتُهُ: see 3. b2: ذَهَنَنِى عَنْهُ, and ↓ أَذْهَنَنِى, and ↓ اِسْتَذْهَنَنِى, He, or it, made me to forget it; diverted me from remembering it: (K, * TA:) [like ذَهَلَنِىعَنْهُ, and أَذْهَلَنِى.] And ذُهِنَ Memory, or understanding, escaped him, or left him. (JK.) 3 ذَاْهَنَ ↓ ذَاهَنَنِى فَذَهَنْتُهُ He vied with me, or contended with me for superiority, in intelligence, understanding, sagacity, acuteness, skill, or knowledge, and I surpassed him [therein, i. e.,] in ذِهْن. (K.) 4 أَذْهَنَ see 1.10 إِسْتَذْهَنَ see 1. b2:  You say also, اِسْتَذْهَنَكَ حُبُّ الدُّنْيَا The love of the present world took away, or has taken away, thy ذِهْن [i. e. intelligence, understanding, &c.]. (TA.) b3:  And اِسْتَذْهَنَتِ السَّنَةُ القَصَبَ (assumed tropical:)  The year of drought took away the ذِهْن, i. e. pith (نِقْى), of the canes, or reeds. (TA.) ذِهْنٌ (JK, S, Msb, K, &c.) and ↓ ذَهَنٌ (S, K) Intellect, intelligence, understanding, sagacity, acuteness, skill, or knowledge; syn. عَقْلٌ, (JK, K,) and فَهْمٌ, (K,) and فِطْنَةٌ, (S, Msb, K,) and ذَكَآءٌ; (Msb;) and retentiveness of mind, or memory: (JK, * S, * K:) or, as some say, a faculty of the soul, provided for the acquisition of the several species of knowledge, including the external and internal senses: strength thereof is termed ذَكَآءٌ: and a good quality thereof for the forming ideas of the things that present themselves to it is termed فِطْنَةٌ: (TA:) pl. أَذْهَانٌ. (Msb, K. *) One says, اِجْعَلْ ذِهْنَكَ إِلَى كَذَا وَكَذَا [Apply thine intellect, &c., to such and such things]. (TA.) [Both are also inf. ns.: see 1, first sentence.] b2:  Also, the former, (assumed tropical:)  Strength: (JK, S, K:) and fat: (JK, K:) pl. as above. (K.) One says, مَا بِرِجْلَىَّ ذِهْنٌ There is not in my legs any strength to walk. (TA.) and هُوَ مِنْ أَهْلِ الذِّهْنِ and الأَذْهَانِ (tropical:)  He is of those endowed with strength [of body: and also, of those endowed with intelligence, &c., and intelligent faculties]. (TA.) And مَا رَأَيْتُ بِالإِبِلِ ذِهْنًا (assumed tropical:)  I  saw not, in the camels, fat and strength. (JK.) b3:  Also (assumed tropical:)  The pith (نِقْى) of canes, or reeds. (TA.) A2:  See also ذَهِنٌ.ذَهَنٌ: see the next preceding paragraph.ذَهِنٌ and ↓ ذِهْنٌ Intelligent, possessed of understanding, sagacious, acute, skilful, or knowing, [and endowed with a retentive mind;] each [said to be] a possessive epithet, [signifying possessing ذِهْن, though the former is agreeable with a general rule as part. n. of ذَهِنَ,] applied to a man; the latter app. changed [or contracted] from the former. (TA.) ذِهْنِىٌّ Of, or relating to, the ذِهْن, or intellect, &c.; intellectual; subjective; ideal. Hence, الأَمُورُ الذِّهْنِيَّةُ Intellectual things; the things that are conceived in the mind, or considered subjectively; opposed to الأَمُورُ الخَارِجِيَّةُ.]