THESAURUS
sit up
abide, arise, await, bide, bide the issue, bristle, cock up, dally, dawdle, delay, dillydally, disentangle, extend, flatten, get up, hang about, hang around, hold everything, hold on, hold your horses, jump up, linger, loiter, mark time, put straight, ramp, rear, rear up, rectify, rise, rise up, set straight, sit bolt upright, sit tight, smooth, stand up, stay, stay up, stick around, stick up, straighten, straighten out, straighten up, take time, tarry, unbend, uncurl, unkink, unsnarl, upheave, uprear, uprise, wait, wait a minute, wait and see
ROGET THESAURUS
sit up
Exertion
VB
exert oneself, exert one's energies, tax one's energies, use exertion, labor, work, toil, moil, sweat, fag, drudge, slave, drag a lengthened chain, wade through, strive, stretch a long arm, pull, tug, ply, ply the oar, tug at the oar, do the work, take the laboring oar bestir oneself (be active), take trouble, trouble oneself, work hard, rough it, put forth one's strength, put forth a strong arm, fall to work, bend the bow, buckle to, set one's shoulder to the wheel, work like a horse, work like a cart horse, work like a galley slave, work like a coal heaver, labor day and night, work day and night, redouble one's efforts, do double duty, work double hours, work double tides,
sit up, burn the candle at both ends, stick to, work one's way, fight one's way, lay about one, hammer at, take pains, do one's best, do one's level best, do one's utmost, give one hundred percent, do the best one can, do all one can, do all in one's power, do as much as in one lies, do what lies in one's power, use one's best endeavor, use one's utmost endeavor, try one's best, try one's utmost, play one's best card, put one's best leg foremost, put one's right leg foremost, have one's whole soul in his work, put all one's strength into, strain every nerve, spare no efforts, spare no pains, go all lengths, go through fire and water, move heaven and earth, leave no stone unturned.
Lateness
VB
be late, tarry, wait, stay, bide, take time, dawdle, linger, loiter, bide one's time, take one's time, gain time, hang fire, stand over, lie over, put off, defer, delay, lay over, suspend, table, shift off, stave off, waive, retard, remand, postpone, adjourn, procrastinate, dally, prolong, protract, spin out, draw out, lengthen out, stretch out, prorogue, keep back, tide over, push to the last, drive to the last, let the matter stand over, reserve, temporize, consult one's pillow, sleep on it, lose an opportunity, be kept waiting, dance attendance, kick one's heels, cool one's heels, faire antichambre, wait impatiently, await,
sit up,
sit up at night.