[General] teaspoonfuls or teaspoonsful

[topcat1957]

As a pharmacist I frequently type directions for measuring doses for liquid medications. Traditionally doctors instruct patients to use a teaspoon as a measuring tool.
I have had arguments with colleagues regarding the proper way to spell the plural for "teaspoonful". I believe the correct spelling is teaspoonfuls.
However others insist it should be 'teaspoonsful'.

Teaspoonful is a term of measurement defined as 5 milliliters or 5ml.

The plural of the word indicates that the measure which is multiplied, not the measurement tool.

If the prescription calls for "1.5 tsps" I contend that it should be written out as "one and one-half teaspoonfuls".


I would greatly appreciate the expert opinion of an English teacher on the matter. Thank you.

 

[Rover_KE]

Welcome to the forum.

Both versions are seen and heard, but 'teaspoonfuls' is more generally preferred.

Click here and here.

 

[GoesStation]

I say one and a half teaspoons.

 

[jutfrank]

I get what you're saying about the measurement being quantified, not the measuring tool. However, teaspoonfuls just sounds wrong to me. I'm guessing that the word developed from the following:

A teaspoon full of sugar
Two teaspoons full of sugar

I suppose this is the reason why teaspoonsful sounds better to many. Because it's grammatical when understood as the above, (as spoken, not written.)

But having said that, why don't you simply say Two teaspoons of sugar, which is easier, neater, and I would argue, more logical?