Disruption of sleep patterns (circadian rhythm) caused by continued computer usage late at night or through interaction with users in different timezones.
I've been on instant messenger with friends in Europe every night this week, and now I'm so netlagged I can't get to sleep before 5 AM.

He had such a severe case of netlag from playing World of Warcraft three nights in a row that he fell asleep in class today.
by Michael Gordon (Zebidee55) October 15, 2008
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Noun: A Netflix induced state of tiredness similar to jetlag
"hey, Emma why were you late today? "

"sorry I stayed up half the night finishing a series, I've got major Netlag"
by gazbo October 23, 2018
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A feeling like jetlag that happens after you use your computer after sunset and the bright backlight tricks your body into thinking it's still daytime.

(For details, google "photoentrainment".)
I was online until midnight last night, and now I feel like I'm still on Tokyo time. Netlag sucks.
by Tom Cohen December 1, 2009
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Netlagged is similar to being Jet lagged. It is fatigue caused by existing in at least three different time zones, whilst chatting on the internet.
Canada to GMT (UK) 6 hours difference behind
GMT (UK) to Indonesia 10 hours difference in front
chatting to people simultaneously would constitute being netlagged.
by RavenPal February 2, 2010
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