[off and on] also [on and off] {adv.}
Not regularly; occasionally; sometimes.
* /Joan wrote to a pen pal in England off and on for several years./* /It rained off and on all day./
- Sometimes used with hyphens like an adjective.
* /A worn-out cord may make a hearing aid work in an off-and-on way./
Compare: BY FITS AND STARTS, FROM TIME TO TIME, NOW AND THEN.