by fits and starts

1. see fits and starts.

2. Also, in fits and starts. With irregular intervals of action and inaction, spasmodically, as in The campaign is proceeding by fits and starts. This expression began in the late 1500s as by fits, the noun fit meaning a “paroxysm” or “seizure”; starts was added about a century later.

Related Words

• erratically 
• fitfully www.thesaurus.com
• haphazardly 
• infrequently www.thesaurus.com
• sporadically 
• unevenly www.thesaurus.com