Lag

Lag \lag\ , verb;
1. To fail to maintain a desired pace or to keep up; fall or stay behind
2. To move or develop slowly, as toward a goal or objective, or in relation to an associated factor
3. To hang back; linger; delay

Sheesh, I am having all kinds of trouble keeping up with this blog these days. Hopefully I'll quit lagging and get caught up soon...no promises, though.

This word as a verb dates to the 1520's from an earlier adjective that meant "last," which dates to the 1510's. It is probably from a Scandinavian language