four-lane (noun) highway: heavily traveled, capacious road
Detalii: a highway is a main road; an expressway is a multilane highway; freeway, parkway, turnpike are types of expressways
Sinonime: ad-lib, dashed off,
extemporaneous, extempore, extemporized,
fake, faked, improv, improviso, off the cuff, offhand, played by ear, shot from the hip, spontaneous, spur-of-the-moment, thrown off, tossed off, unpremeditated, unprepared, unscripted, unstudied, vamped, whipped up,
winged*
Antonime: deliberate, designed, planned, premeditated, rehearsed