جثل1 جَثُلَ, aor. ـُ (Lth, Msb, K;) and جَثِلَ, aor. ـَ (K;) inf. n. جُثُولَةٌ and جَثَالَةٌ; (Msb, K;) both of the former verb; (Msb, TA;) [but both mentioned in the S as simple substs.;] It was, or became, such as is termed جَثْلٌ, explained below. (Msb, K.) Q. Q. 4 اِجْثَأَلَّ He (a bird) ruffled his feathers (S, K) by reason of the cold. (TA.) b2:  (assumed tropical:)  He (a man) became angry, and prepared himself for fighting. (S, K.) b3:  (assumed tropical:)  It (a plant, or herbage,) became tall, and tangled, or luxuriant, or abundant and dense: (Z, K:) or became tall (اِهْتَزَّ, q. v.), and such as might be grasped with the hand. (Az, S, K.) b4:  It (the plumage of a bird) became ruffled. (K.) جَثْلٌ (Az, S, Msb, K) and ↓ جَثِيلٌ (K) A thing, (Msb,) or hair, (Az, S, K,) and (tropical:)  trees (شَجَرٌ), (K, TA,) much, or abundant, (Az, S, Msb, K,) and thick, or abundant, (Az, S, Msb, K,) and thick, or coarse, or rough, (Msb,) or tangled, or luxuriant and dense, (K,) and soft: (TA:) or thick, or coarse, or rough, and short: or dense and black: (K:) or the blackest hair: or the thickest, or coarsest, or roughest: (Lth, TA:) or anything large, big, or bulky, and dense, and tangled, or luxuriant. (K.) You say لِحْيَةٌ An abundant, thick, or coarse, or rough, beard. (Msb:) or a thick, or dense, beard. (TA.) and نَاصِيَةٌ جَثْلَةٌ A horse's forelock moderate in respect of quantity and length: such is approved. (S.) And شَجَرَةٌ جَثْلَةٌ (tropical:)  A many-leaved, big, tree. (S, K, TA.) A2:  جَثْلٌ A species of ant, large and black; as also جَفْلٌ: (IDrd, TA:) or جَثْلَةٌ signifies a black ant: (S:) or a large and: and جَثْلٌ is its pl. [or coll. gen. n.]. (K.) جَثَيلٌ: see جَثْلٌ.جُثَالَةٌ Leaves that have become gradually scattered, or strewn. (K.) مُجْثَئِلٌّ Brood, or wide. (K.) b2: Standing erect. (S, K.)