Words about music: （音楽に関する用語）

Accent [like legato,staccato] = アクセント記号（レガート、スタッカート等）
Accidental [sharp, flat, dble-sharp...] = 臨時記号
Bar [also called measure] = 小節
Bar line [vertical line which separates two bars] = 縦線
[To] Blow [in an harmonica, when emptying one's lungs] = 吹く
Bass clef = ヘ音記号（低音部記号）
Bracket = 括弧
Break symbol [see note above] = 構成記号
Cell [free space between frets under guitar strings] = セル
Chord [several notes at the same time] = コード
Chord diagram [guitar] = コード・ダイアグラム
Clef [bass or treble clef at the beginning of the staff] = 音部記号
[Chord] Diagram = ダイアグラム
Dot = 付点
Dotted Note = 付点音符
Double-flat [accidental] = ダブルフラット
Double-sharp [accidental] = ダブルシャープ
[To] Draw [in an harmonica, when filling one's lungs] = 吸う
Drum = ドラム
Drums = ドラム
Duration = （音符等の）長さ（音価）
Dynamics [like forte, mezzo forte, etc...] = 強弱記号
Effect [applied to a note, such as vibrato, slide...] = エフェクト（奏法）
Enharmonic = 異名同音（Ｇ♭とＦ♯など）
Flat [accidental] = フラット（♭）
Fret [on a guitar neck, metal bar which separates cells] = フレット
Ghost rest [can also be translated as "virtual rest"] = 仮想休止（要定義）
Grace notes [appoggiaturas] = 装飾音
Grace notes after [Acciacatura] = 中間打音
Hitch = 連桁する
Hitched notes = 連桁（れんこう）
Instrument = 楽器
Inversion [other way to write the same chord by inverting notes] = 転回
Key [signature (sharps or flats near the clef symbol)] = キー（調号）
Lyrics = 歌詞
Major [chord] = メジャー
Metronome = メトロノーム
Minor [chord] = マイナー
Natural [for an accidental] = ナチュラル
Note = 音符
Octave = オクターブ
Ornaments = 装飾記号（トリルなど）
Pitch [note frequency] = ピッチ
Pressure time = 打鍵時間
Quantize = クオンタイズ
Relate/Associate [to link an instrument to a staff] = 楽器の割り当て
Rest [silent note] = 休止符／休符（無音の音符）
Score [your document, with several staves] = スコア（総譜）
Semitone = 半音
Sharp [accidental] = シャープ（♯）
Slur [Symbol which ties notes with different pitches] = スラー
Staff [six horizontal line + a clef. Plur. : staves] = 譜表
Stem length = 符幹の長さ（おたまじゃくしの「ぼう」の長さ）
Stem direction = 符幹の向き（おたまじゃくしの「ぼう」の上下方向）
Treble clef = ト音記号（高音部記号）
Velocity [note strength] = べロシティ（打鍵強度）
Tablature [for guitar] = タブ譜（奏譜）
[To] Transpose = 移調する
Transposition = 移調
Triplet = 三連符
[To] Tie [horizontal parenthesis to add consecutive notes durations] = タイ
Transposable = 移調可能な
Tune = 曲
Tuplet = 連符

[Note lengths (durations)] （音符の長さ）
Whole note = 全音符
Half note = 二分音符
Quarter [note] = 四分音符
Eighth [note] = 八分音符
16th = 十六分音符
32nd = 三十二分音符
64th = 六十四分音符