centenary

at fixed intervals

done or occurring every hour

at fixed intervals

done, happening etc once a month; valid for one month

at fixed intervals

of, concerning, an orbit; a circular motorway round a city (e.g. the London Orbital)

at fixed intervals

occurring or appearing at regular intervals

at fixed intervals

irregular; happening in, affected by, spasms

twitching, erratic

happening occasionally

on and off

(of the skin) having spots

blotchy, irregular