Beware, older languages below! The languages below were invented during Tolkien's earlier period and should be used with caution. Remember to never, ever mix words from different languages!

Qenya 

sak-

verb. to hurt

A verb for “to hurt” appearing only in the form sakin “hurts me” in a marginal note within the Quenya Verbal System (QVS) from 1948 (PE22/93 note #6). This note was later struck through (PE22/93 note #7), but there are hints of this verb’s continued existence in the possibly-related adjective sahta “marred” from the late 1950s (MR/405).

Neo-Quenya: Given sahta “marred”, I would also retain ᴺQ. sac- “to hurt” for purposes of Neo-Quenya.