ROCKILY
Etymology
Adverb
rockily (comparative more rockily, superlative most rockily)
In an uneven way; in a rocking manner.
In a manner suggestive of a rock or rocks.
Unsteadily; inconsistently or resulting in volatility.
In a manner suggestive of rock music.
Top of the three here is āTon Of Loveā, a back beaten Tom Petty-ish album tracker with Beach Boy backing vox, slick and, get this, rockily abrasive.
Source: Wiktionary
ROCKY
Rock"y, a.
1. Full of, or abounding in, rocks; consisting of rocks; as, a rocky
mountain; a rocky shore.
2. Like a rock; as, the rocky orb of a shield. Milton.
3. Fig.: Not easily impressed or affected; hard; unfeeling; obdurate;
as, a rocky bosom. Shak. Rocky Mountain locust (Zoƶl.), the Western
locust, or grasshopper. See Grasshopper.
– Rocky Mountain sheep. (Zoƶl.) See Bighorn.
Source: Webster’s Unabridged Dictionary 1913 Edition