|Easton's Bible Dictionary|
Only in the title of Psalm 5. It is probably derived from a root meaning "to bore," "perforate," and hence denotes perforated wind instruments of all kinds. The psalm may be thus regarded as addressed to the conductor of the temple choir which played on flutes and such-like instruments.
Noah Webster's Dictionary
(n. pl.) A term supposed to mean, perforated wind instruments of music, as pipes or flutes.
Int. Standard Bible Encyclopedia
ne-hil'-oth, ne'-hi-loth (Psalm 5, title). See MUSIC.
Nehiloth (2 Occurrences)
Psalms 4:8 In peace will I both lay me down and sleep; For thou, Jehovah, alone makest me dwell in safety. Psalm 5 For the Chief Musician; with the Nehiloth. A Psalm of David. (ASV)
Psalms 5:1 Give ear to my words, O Jehovah, Consider my meditation. (See JPS DBY WBS)