supposing - Wiktionary, the free dictionary

• (General American) IPA^(key): /səˈpoʊzɪŋ/
• (Received Pronunciation) IPA^(key): /səˈpəʊzɪŋ/
• Rhymes: -əʊzɪŋ
• Hyphenation: sup‧pos‧ing

supposing

1. present participle and gerund of suppose

supposing (plural supposings)

1. The act of making a supposition.

   • 1837, The Dublin University Magazine:

     She could have joined most comfortably in all their supposings, and suspicions, and doubts, and prognostications, but the honour of the family was too nearly concerned to allow free reins to her tongue.

supposing

1. if hypothetically (optionally followed by that)

   • 2013, Flora Annie Steel, “The Three Sillies”, in English Fairy Tales‎^[1]:

     Supposing our daughter was to marry her sweetheart, and supposing they was to have a son, and supposing he was to grow to man’s estate, and supposing he was to come down to draw cider like as we’re doing, and supposing that there mallet was to fall on his head and kill him, how dreadful it would be!