lag:
(also ‘laggard’; plural: ‘lags‘)

a lag, lagging behind other runners
a person (or thing) that is very slow to do or to react to something (because the person is either tired or uninterested in doing);
someone who is always late for something;
a person who lags; a straggler;
a convict or an ex-convict,

a lag in a horse race
Jane is such a lag… always late for her school, outing and even dinner.
As a high school teacher for may years, Mary has seen many lags in her students — children who find it difficult to do certain academic activities as fast as other normal children.
All our fielders are in good shape, except those two lags, Nick and Pete, who somehow find it difficult to react quickly to counter their opponents.
There is a special wing in the police department which is designed to keep track of old lags who have just served their time in prison but might fall back into old habits and commit crimes again.
Note 2: ‘Lag’ is also used in computer terminology. For an article that explains what lag in computers is, please click here.
Note 3: ‘Jet lag’ is a medical condition a man experiences when he travels long distances on a jet plane crossing time-zones. For a medical article that explains what ‘jet lag’ is, please click here.
