or is that "day of the week"?

Yes, that would be day of the week. Here’s an example: 4, Monday, December, 2019 = 12/23/19

There's no native support for week number in

Date

as far as I know. You could do this using

moment.js

though:

let theDay = moment("4, Monday, December, 2019", "w, dddd, MMMM, YYYY");

See https://momentjs.com/docs/#/parsing/string-format/

thank you, Eric! looks like we will need to derive the week number for the year (ie. 54 instead of 4 for December) and then use moment to get the date

oh yeah, I don't know any date formats that support "week of the month"