breast pump
Specifically a device for expressing breast milk; commonly used in parenting and medical contexts.
See also: 搾乳
I learned how to use a breast pump at the maternity hospital.
milking machine; milking device
General term for any mechanical milking apparatus, including those used in dairy farming.
The dairy farmer introduced a new milking machine.
搾乳 refers to the act of milking or pumping, while 搾乳機 is the machine or device (e.g. a breast pump) used to perform it.
Standard kanji spelling for a milking device, including breast pumps.
Alternate spelling using 機 (machine); equally valid but less common than 器.
Mixed kana-kanji spelling; often used in medical or product contexts for breast pumps.
Compound of 搾乳 (milking) + 器 (device). The exact historical origin is uncertain, but the kanji composition transparently reflects the meaning.