Spasmodic

1. Of or relating to a spasm; resembling a sudden contraction of the muscles.
2. Convulsive; consisting of spasms.
3. Intermittent or fitful; occurring in abrupt bursts.

Synonyms: patchy, stop-start; see also Thesaurus:discontinuous

4. Erratic or unsustained.
5. Of or relating to the spasmodic poets, a group of British Victorian poets who wrote introspective drama in verse.