In a longing manner, with desire, yearningly.(adverb)
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Use "longingly" in a sentence
"I would gaze longingly from the speeding train to a little joint just off the tracks in Hillsdale, remarking to my colleagues every time we left Sunnyvale that someone had to go there with me for a cheeky martini."
"It’ll clock in at only 90 seconds long and, as for what it will contain, werewolves, vampires, and Bella looking at one of those two possibilities longingly is a sure bet."
"I told him I wanted to marry him (the Chef) but I think he may have been gay because he kept looking at Gil longingly, which is probably a good thing because I would weigh 300 pounds if I married him because everything he made was orgasmic."