unsteady (adj.) Look up unsteady at Dictionary.com
1590s, "not firm or secure in position," from un- (1) "not" + steady (adj.). Similar formation in Old Frisian unstadich, German unstätig, Middle Dutch onstadich. Meaning "marked by irregularity" is from 1680s. Related: Unsteadily (1550s).
unsteady (v.) Look up unsteady at Dictionary.com
"make unsteady," 1530s, from un- (2) "reverse, opposite of" + steady (v.). Related: Unsteadied; unsteadying.