(pathology) An arrhythmia presumably caused by a malfunction of the sinus node, the heart's primary pacemaker.

(roofing, nautical) The degradation of the roofing nails of a house or the nails of a boat, necessitating repair.

plural of side hustle

(idiomatic) To do or experience something exceedingly difficult or rare.

alternative form of sidetrack

plural of side track

In someone's good graces; approved of by someone; not having annoyed or irritated someone.

(born) illegitimately, outside of wedlock

Alternative form of darkside

(slang, UK, Australia, New Zealand) To be received very poorly; to be highly unpopular.