Understandingly

Tom nodded understandingly.

Tom smiled understandingly.

Our eyes are opened to see other colors than purple and gold, our ears to hear understandingly other sounds than the roar of traffic, the shriek of an automobile horn, or syncopated music.

[T]he proprietor smiled understandingly.

Garcias ab Horto writes of one whom he saw at Goa in the East Indies, that took ten drams of opium in three days; and yet consulto loquebatur, spake understandingly […]