I've answerd this question here under my old username:

Yes, dildo was used in the modern sense by the sixteenth and seventeenth centuries. Compare Rochester's poem, Signor Dildo in 1673

[G]o thither to make your Selfes Sweet,

By Buying of Powder, Gloves, Essence, or Soe

You may Chance get a Sight of Signior Dildo.

You’l take him at first for no Person of Note

Because he appears in a plain Leather Coat:

But when you his virtuous Abilities know

You’ll fall down and Worship Signior Dildo.

Or, even earlier, Nashes Dildoe dated around 1620, wherein the male protagonist leaves his partner unsatisfied and she takes out “my little dildo…that bendeth not / and stands as stiff as he were made of steele.” She says that her glass friend “refreshes her well / and never makes my tender belly swell [with a child].”

The 'fine dog with the hole in his head' likely refers to the fact that the higher-quality dildoes were supposed to shoot fluid out of them (warm milk is commonly suggested), it was seen as essential to women's pleasure. See this example of a high end 17th century dildo that had this feature: https://imgur.com/43G7nab There are a number of engravings (that I don't have on me right now) that show women's maids helping them with the pump action of these dildos.

To quote also from Sarah Toulanan:

But the pleasure gained from the use of such implements was inferior to the pleasure of using a dildo that also had some mechanism for emitting a semen-like fluid. Susanne relates a story that she claims to have read in a history book ‘about a king’s daughter who made use of a pleasant device instead of a real man’. This woman used a bronze replica of a man, which had a life-like penis made of some other, softer material, and which could also be made to emit a semen-like substance when desired: ‘At the moment of orgasm she turned a certain knob which protruded from the rump of the statue so that its member squirted a non-stop flow of a certain warm, thick, and white liquid—like a gruel—into the girl’s cunny, which irrigated her and provided a satisfactory form of intercourse.’⁷²