tasya sanjanayanharsam kuruvrddhah pitamahah
simhanadam vinadyoccaih sankham dadhmau pratapavan
The grand old man or the Kaurava race, their glorious grand-uncle Bhisma, cheering Duryodhana roared loudly like a lion, and blew. his conch. 12
Tanya sanjanayanharsam:-Here, it should have been said, that Bhisma blew his conch and it cheered Duryodhana. But it is said that Bhisma, cheering up Duryodhana, blew his conch. Sanjaya wants to state that the very action of blowing the conch, will certainly cheer up Duryodhana. To express this influence of Bhisma, Sanjaya uses the adjective 'Pratapavan' (glorious).
Karuvrddhah:-Though in the Kum face Bahlika (the younger brother of Bhisma father Santanu), was older than Bhisma, yet Bhisma, possessed better knowledge of righteousness and God, than all other old members, in the race. So Sanjaya, calls him 'Kumvrddhah', (the grand old man of the Kaurava race).
Pratapavan:- Bhisma was well-known for his renunciation of wealth and woman i.e., he did not accept any kingdom nor did he marry. He was well-versed in military science and scriptures. So the warrior class were very much influenced by him.
When Bhisma for his brother Vicitravirya kidnapped all by himself, the daughters of the king of Kati, from the place where their suitors had assembled to marry them, the Ksatriya suitors attacked him, but he alone defeated all of them. He was so well-versed, in the science of weapons and warfare, that he did not accept his defeat even against his preceptor Parasurama, who had taught him the science of weapons etc. Thus he had great influence over the Ksatriyas (warrior class), because of his skill in military science.
When Bhisma was lying on a bed of arrows Lord Krsna said to Yudhisthira, "If you want to put any question on righteousness (Dharma), ask him now, because the sun of the knowledge of scriptures, is going to set, i.e., Bhisma, a great scholar of scriptures is going to die." Thus, we see that he had great mastery over the scriptures and others were very much influenced by this knowledge.
Pitamahah:-This word seems to mean that Dronacarya did not attach any importance to the tricks played by Duryodhana. He understood that Duryodhana wanted to deceive him. So he remained silent. But Bhisma is the grand-uncle of Duryodhana. So he sees Duryodhana's child-likc behaviour, in his tricks. Hence Bhisma unlike Dronacarya, breaks his silence and blows his conch to cheer up Duryodhana, and show his affection for him.
Simhanadam vinadyoccaih sankham dadhmau:-When a lion roars ferociously, even large wild animals like elephants etc., get horror-struck. Similarly, by roaring ferociously, Bhisma blew his conch to cheer up Duryodhana, and terrorise the warriors, of the hostile army.
Appendix:-Duryodhana's relationship with Dronacarya was that of pupil-teacher while with Bhisma he had the family relationship. Where there is the pupil-teacher relationship, there is no partiality but in family relationship because of the affection for the family, partiality ensues. Therefore having heard the tricky words uttered by Duryodhana, Dronacarya remained quiet which discouraged Duryodhana. But because of family-affection, having seen Duryodhana sad, Bhisma blew the conch in order to encourage Duryodhana.