Holy Mole said:
No...a bow is a tie..
.... or a gesture of respect
.....or even possibly an altering of a shape under a force
but by NO means could it be a weapon that thrusts sharpened aerodynamic objects using tension.
Your condescension noted, the fact of the matter is that the word translated as "bow" has a variety of interpretations (based on context), one of which might be relating to a musical dirge, hence the alternative translations....
(ASV) (and he bade them teach the children of Judah the song of the bow: behold, it is written in the book of Jashar):
(CEV) and he ordered his men to teach the song to everyone in Judah. He called it "The Song of the Bow," and it can be found in The Book of Jashar. This is the song:
(ERV) David told his men to teach the song to the people of Judah. This song is called The Bow, and it is written in the Book of Jashar.
(LITV) and he said to teach the sons of Judah The Song of the Bow. Behold, it is written in the Book of Jashar:
(RV) And he bade them teach the children of Judah the song of the bow: behold, it is written in the book of Jashar.
Barnes
2 Samuel 1:18
The use of the bow - Omit “the use of.†“The bow†is the name by which this dirge was known, being so called from the mention of Jonathan’s bow in 2Sa_1:22. The sense would then be: And he commanded them to teach the children of Israel the song called Kasheth (the bow), i. e. he gave directions that the song should be learned by heart (compare Deu_31:19). It has been further suggested that in the Book of Jasher there was, among other things, a collection of poems, in which special mention was made of the bow. This was one of them. 1Sa_2:1-10 was another; Num_21:27-30 was another; Lam. 2 was another; Lam. 3 was another; Jacob’s blessing Gen. 49; Moses’ song Deut. 32; perhaps his Blessing (Deut. 33. See 2 Sam. 1:29); and such Psalms as Ps. 44; Psa_46:1-11; Psa_76:1-12, etc.; Hab. 3; and Zec_9:9-17, also belonged to it. The title by which all the poems in this collection were distinguished was קשׁת qesheth, “the bow.†When therefore the writer of 2 Samuel transferred this dirge from the Book of Jasher to his own pages, he transferred it, as we might do any of the Psalms, with its title.
Clarke
2 Samuel 1:18
The use of the bow - The use of is not in the Hebrew; it is simply the bow, that is, a song thus entitled. See the observations at the end, 2Sa_1:21 (note).
In other words, there is great possibility that the difficult passage has more than a reasonable chance of being associated with teaching a song of lamentations.