In Tkinter is there any way to make a widget invisible?

I'm also extremely late to the party, but I'll leave my version of the answer here for others who may have gotten here, like I did, searching for how to hide something that was placed on the screen with the .place() function, and not .pack() neither .grid().

In short, you can hide a widget by setting the width and height to zero, like this:

widget.place(anchor="nw", x=0, y=0, width=0, height=0)

To give a bit of context so you can see what my requirement was and how I got here. In my program, I have a window that needs to display several things that I've organized into 2 frames, something like this:

[WINDOW - app]
  [FRAME 1 - hMainWndFrame]
    [Buttons and other controls (widgets)]
  [FRAME 2 - hJTensWndFrame]
    [other Buttons and controls (widgets)]

Only one frame needs to be visible at a time, so on application initialisation, i have something like this:

hMainWndFrame = Frame(app, bg="#aababd")
hMainWndFrame.place(anchor="nw", x=0, y=0, width=480, height=320)
...
hJTensWndFrame = Frame(app, bg="#aababd")

I'm using .place() instead of .pack() or .grid() because i specifically want to set precise coordinates on the window for each widget. So, when i want to hide the main frame and display the other one (along with all the other controls), all i have to do is call the .place() function again, on each frame, but specifying zero for width and height for the one i want to hide and the necessary width and height for the one i want to show, such as:

hMainWndFrame.place(anchor="nw", x=0, y=0, width=0, height=0)
hJTensWndFrame.place(anchor="nw", x=0, y=0, width=480, height=320)

Now it's true, I only tested this on Frames, not on other widgets, but I guess it should work on everything.

For hiding a widget you can use function pack_forget() and to again show it you can use pack() function and implement them both in separate functions.

from Tkinter import *
root = Tk()
label=Label(root,text="I was Hidden")
def labelactive():
    label.pack()
def labeldeactive():
    label.pack_forget()
Button(root,text="Show",command=labelactive).pack()
Button(root,text="Hide",command=labeldeactive).pack()
root.mainloop()

I was not using grid or pack.
I used just place for my widgets as their size and positioning was fixed.
I wanted to implement hide/show functionality on frame.
Here is demo

from tkinter import *
window=Tk()
window.geometry("1366x768+1+1")
def toggle_graph_visibility():
    graph_state_chosen=show_graph_checkbox_value.get()
    if graph_state_chosen==0:
        frame.place_forget()
    else:
        frame.place(x=1025,y=165)
score_pixel = PhotoImage(width=300, height=430)
show_graph_checkbox_value = IntVar(value=1)
frame=Frame(window,width=300,height=430)
graph_canvas = Canvas(frame, width = 300, height = 430,scrollregion=(0,0,300,300))
my_canvas=graph_canvas.create_image(20, 20, anchor=NW, image=score_pixel)
vbar=Scrollbar(frame,orient=VERTICAL)
vbar.config(command=graph_canvas.yview)
vbar.pack(side=RIGHT,fill=Y)
graph_canvas.config(yscrollcommand=vbar.set)
graph_canvas.pack(side=LEFT,expand=True,fill=BOTH)
frame.place(x=1025,y=165)
Checkbutton(window, text="show graph",variable=show_graph_checkbox_value,command=toggle_graph_visibility).place(x=900,y=165)
window.mainloop()

Note that in above example when 'show graph' is ticked then there is vertical scrollbar.
Graph disappears when checkbox is unselected.
I was fitting some bar graph in that area which I have not shown to keep example simple.
Most important thing to learn from above is the use of frame.place_forget() to hide and frame.place(x=x_pos,y=y_pos) to show back the content.

For someone who hate OOP like me (This is based on Bryan Oakley's answer)

import tkinter as tk

def show_label():
    label1.lift()

def hide_label():
    label1.lower()

root = tk.Tk()
frame1 = tk.Frame(root)
frame1.pack()

label1 = tk.Label(root, text="Hello, world")
label1.pack(in_=frame1)

button1 = tk.Button(root, text="Click to hide label",command=hide_label)
button2 = tk.Button(root, text="Click to show label", command=show_label)
button1.pack(in_=frame1)
button2.pack(in_=frame1)

root.mainloop()

import tkinter as tk
...
x = tk.Label(text='Hello', visible=True)
def visiblelabel(lb, visible):
    lb.config(visible=visible)
visiblelabel(x, False)  # Hide
visiblelabel(x, True)  # Show

P.S. config can change any attribute:

x.config(text='Hello')  # Text: Hello
x.config(text='Bye', font=('Arial', 20, 'bold'))  # Text: Bye, Font: Arial Bold 20
x.config(bg='red', fg='white')  # Background: red, Foreground: white

It's a bypass of StringVar, IntVar etc.