sporadic

Etymology

From Medieval Latin sporadicus (whence also French sporadique, Italian sporadico, Spanish esporádico), from Ancient Greek σποραδικός (sporadikós), from σποράς (sporás, “scattered, dispersed”), from σπορά (sporá), σπόρος (spóros, “a sowing [of seed]”).

adj

1. (archaic) (of diseases) occurring in isolated instances; not epidemic.
2. Rare and scattered in occurrence.
   It was a stodgy, weary display from Mourinho’s team with only sporadic moments when they threatened Salvatore Sirigu’s goal and their manager seemed bewildered afterwards when he tried to explain what had gone wrong. 12 March 2015, Daniel Taylor, “Chelsea out of Champions League after Thiago Silva sends 10-man PSG through on away goals”, in The Guardian (London)
3. Exhibiting random behavior; patternless.