The word attack is fully correct. Maybe it is a good idea to additionally explain this: It does not matter which instrument is being used. So the context from this respect is irrelevant. The piano, violin, flute, clarinet, guitar etc. Even the human voice itself. Attack is a common word for explaining the "timing" of a note being produced. How and which instrument is being used matters when it comes to the technique of producing the note respectively the sound. So attack changes its tone, not pitch amplitude, tempo etc. If the player of an instrument is gifted they will not glide to other notes without the proper fading after attack of the original. If they do it will sound disharmonious as well as out of timing to the less gifted ear. If the player of the instrument is very bad with playing by notes the attack issue turns more and more into a tempo problem rather than a tone and pitch issue. Same with singers, timing of breath commencement and producing the note and fading according to rules of harmony will be a good step to becoming virtuoso. Provided they have a voice gifted by nature in the first place. Otherwise everyone is anyhow a bathroom singer who sounds good to themselves within the echoing effect of the walls and their own ears.