"left axis" is correct and usable in written English.
You may use it when describing a type of movement or positioning. For example, "The dancer spun gracefully on the left axis."
(c) Left axis: fractional occupancy of SIII′ sites by K+ cations indicating blockage of 8MR pores over the experimental temperature range.
In subgroup analyses of young patients, African-American subjects and subjects without left axis deviation (LAD), IIIQ+S remained associated with HCM.
Volume measured on left axis, open interest on the right axis.
Electrocardiography showed left axis deviation and poor R wave progression.
(B ) Time-averaged firing rates for seven different networks during PI control (left axis, colors).
ECG abnormalities at baseline included left axis deviation, signs of LV hypertrophy, conduction delay (QRS >110 ms), and microvoltage in standard leads.
Left axis deviation was defined as a QRS axis more negative than −30° and right axis deviation as a QRS axis more positive than +120°.
Further assessment at 2 months had revealed a bradycardic heart rate of 75 bpm, QTc prolongation, left axis deviation, and left anterior fascicular block (LAFB).
The bars show the percentage of women in each behavioural outcome category reporting at least one ANC visit (left axis scale).
